bearing clearances

[grumpyvette]

Rod bearings 0.002 - 0.025" , side clearance 0.010 - 0.020"

Main bearings 0.002 - 0.003" for most engines ( 0.020-0.025 bearing clearance on small blocks, .025-.027 bearing clearance is about ideal, on big blocks ), 0.005 - 0.007 crankshaft end play

On clearances; the industry standard for performance clearances has long time been .001" for every 1" of shaft diameter. For a BB Chev 2.75 main journal, that's .0027" clearance. .0025 is on the tight side and I wouldn't run anything that tight that's going to spin any considerable rpm or or make any considerable power. The more power and rpm you make, the more parts are going to flex and take up the needed space to form an effective oil wedge. Running more clearance than necessary is a little added insurance, but also means more oil volume needed and more free oil flying around in the crankcase, more work for the oil pump, and more windage issues to deal with.

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this is rather good advise, but consider the bearing clearance must be checked carefully and verified, and the crank journals must be carefully checked for taper, roundness finish and journals must be concentric

Piston to head clearance 0.038 MINIMUM including gasket (.038-.042 quench is what you want with steel rods)(steel rods), 0.060" MINIMUM quench aluminum rods

Valve to piston clearance MINIMUM 0.100" exhaust , 0.080" intake NO VALVE FLOAT
Recommended: 0.080 intake, 0.100 Exhaust (steel rods) 0.100 intake, 0.120 Exhaust aluminum rods
TORQUE SPECS CAN BE FOUND HERE IN THIS LINK
http://garage.grumpysperformance.com/index.php?threads/torque-specs-calculator-links-etc.1222/

http://garage.grumpysperformance.com/index.php?threads/rotating-assembly-bearings.9527/
together correctly

http://www.harborfreight.com/36-piece-3 ... 60669.html

watch this video

Chevy V8 bore & stroke chart
always accurately measure the crank main journals, and remember the crank and block bearing sizes on a 400 sbc and 350 smc are different as are the early 283-327 sbc

Chevy V8 Crankshaft Journal Sizes

Here's a list of Chevy V-8 crankshaft journal sizes. All journal sizes are given in "STANDARD" sizes. Your crankshaft may have been cut down in size previously by a machine shop. Make sure your crank will work in the block you have. Blocks were made for each crank main journal size. If you are putting a "small" or "medium" journal smallblock crank into a "medium" or "large" journal smallblock block you will need crank bearing "spacers" or use special "thick" bearings available from aftermarket suppliers.

Chevy Smallblock V8 Crankshaft Journal Sizes


Gen.I, "Small Journal"
265...Mains-2.30"-Rods-2.00"
283...Mains-2.30"-Rods-2.00"
302...Mains-2.30"-Rods-2.00"
327...Mains-2.30"-Rods-2.00"



Gen.I, "Medium Journal", includes "Vortec" 305 and 350 thru '98
262...Mains-2.45"-Rods-2.10"
267...Mains-2.45"-Rods-2.10"
302...Mains-2.45"-Rods-2.10"
305...Mains-2.45"-Rods-2.10"
307...Mains-2.45"-Rods-2.10"
327...Mains-2.45"-Rods-2.10"
350...Mains-2.45"-Rods-2.10"



Gen.I, "Large Journal"
400...Mains-2.65"-rods-2.10"



Non-production Gen.I combination, using Gen.I 400 crank in Gen.I 350 block
383...400 crank, Mains cut to 2.45"-Rods-2.10"



Non-production Gen.I combination, using Gen.I 350 crank in Gen.I 400 block
377..."Spacer" or "thick" main bearings with 350 crank-Rods-2.10"



Gen.II, "Medium Journal", includes "L-99" 265, "LT-1" 350, "LT-4" 350
265...Mains-2.45"-rods-2.10"
305...Mains-2.45"-Rods-2.10"
350...Mains-2.45"-Rods-2.10"



Non-production Gen.II combination, using Gen.II 265 "L-99" crank in Gen.II 350 block
302...Mains-2.45"-Rods-2.10"



Gen.III, includes '97-2005 "LS-1" Corvette, Firebird, Camaro
345...Mains-2.558"-Rods-2.10"



Corvette "ZR-1", DOHC, "LT-5"
350...Mains-2.76"-Rods-2.10"

CID BORE STROKE
262 = 3.671" x 3.10" (Gen. I, 5.7" rod)
265 = 3.750" x 3.00" ('55-'57 Gen.I, 5.7" rod)
265 = 3.750" x 3.00" ('94-'96 Gen.II, 4.3 liter V-8 "L99", 5.94" rod)
267 = 3.500" x 3.48" (Gen.I, 5.7" rod)
283 = 3.875" x 3.00" (Gen.I, 5.7" rod)
293 = 3.779" x 3.27" ('99-later, Gen.III, "LR4" 4.8 Liter Vortec, 6.278" rod)
302 = 4.000" x 3.00" (Gen.I, 5.7" rod)
305 = 3.736" x 3.48" (Gen.I, 5.7" rod)
307 = 3.875" x 3.25" (Gen.I, 5.7" rod)
325 = 3.779" x 3.622" ('99-later, Gen.III, "LM7", "LS4 front wheel drive V-8" 5.3 Liter Vortec, 6.098" rod)
327 = 4.000" x 3.25" (Gen.I, 5.7" rod)
345 = 3.893" x 3.622" ('97-later, Gen.III, "LS1", 6.098" rod)
350 = 4.000" x 3.48" (Gen.I, 5.7" rod)
350 = 4.000" x 3.48" ('96-'01, Gen. I, Vortec, 5.7" rod)
350 = 3.900" x 3.66" ('89-'95, "LT5", in "ZR1" Corvette 32-valve DOHC, 5.74" rod)
364 = 4.000" x 3.622" ('99-later, Gen.III, "LS2", "LQ4" 6.0 Liter Vortec, 6.098" rod)
376 = 4.065" x 3.622" (2007-later, Gen. IV, "L92", Cadillac Escalade, GMC Yukon)
383 = 4.000" x 3.80" ('00, "HT 383", Gen.I truck crate motor, 5.7" rod)
400 = 4.125" x 3.75" (Gen.I, 5.565" rod)
427 = 4.125" x 4.00" (2006 Gen.IV, LS7 SBC, titanium rods)

Two common, non-factory smallblock combinations:

377 = 4.155" x 3.48" (5.7" or 6.00" rod)
400 block and a 350 crank with "spacer" main bearings
383 = 4.030" x 3.75" (5.565" or 5.7" or 6.0" rod)
350 block and a 400 crank, main bearing crank journals
cut to 350 size

ALL production big blocks used a 6.135" length rod.
CHEVY BIG BLOCK V-8 BORE AND STROKE


366T = 3.935" x 3.76"
396 = 4.096" x 3.76"
402 = 4.125" x 3.76"
427 = 4.250" x 3.76"
427T = 4.250" x 3.76"
454 = 4.250" x 4.00"
477= 4.5" bore x 3.76" stroke
496 = 4.250" x 4.37" (2001 Vortec 8100, 8.1 liter)
502 = 4.466" x 4.00"
557T= 4.5 bore 4.375" stroke
572T = 4.560" x 4.375" (2003 "ZZ572" crate motors)

T = Tall Deck

ALL production big blocks used a 6.135" length rod.


MEASURE CAREFULLY

http://garage.grumpysperformance.co...ting-resistance-to-look-for.11312/#post-51472

the most important and effective performance asset you have is simply your ability to ask yourself questions, the ability to think logically isolate and test components carefully and doing the research if its required to find the best answer's you'll need.

its the attention to details and checking clearance etc. and time and care taken,
that makes the difference between a barely or average functional ,
and a rather exceptional engine build, yes the urge to get it running is strong,
but getting it done correctly is the goal

Plastic gauge?

Question: Can plastic gauge read correctly if used on a crank already oiled or with assembly lube?? I am wanting to confirm the work done by my machine shop but I do not want to tear it down and dry it off, just see if they did the clearances correctly. I figure to check one or two main caps...

garage.grumpysperformance.com

http://garage.grumpysperformance.co...ting-resistance-to-look-for.11312/#post-51472

yes I use both micrometers and snap gauges and cross check with plasti-gauge
and yes when you compare the crushed width of the plasti-gauge youll find it rarely falls as an exact match to the bar chart tape that is packaged with it so you can judge clearance based on crush width
http://garage.grumpysperformance.com/index.php?threads/bearing-clearances.2726/

failure to take the time and effort to read the sub linked info,
WILL usually result in
significantly increased cost and delays in engine assembly!
yes Ive seen several cases where guys failed to install the oil pump pick-up at the proper minimum 3/8"-to-1/2" off the oil pan floor clearance,
the result is the pump is starved for oil intake flow.

http://garage.grumpysperformance.co...m-sure-your-convinced-its-the-oil-pump.11085/

http://garage.grumpysperformance.co...m-oil-pump-installed-now-no-oil-pressure.525/

http://garage.grumpysperformance.com/index.php?threads/bbc-oil-pump-in-a-sbc.2598/
viewtopic.php?f=53&t=852&p=1311&hilit=checking+bearings#p1311

https://www.fordmuscle.com/fundamentals/plastiguage/



http://www.autozone.com/test-scan-and-s ... 36168_0_0/

http://www.hotrod.com/how-to/additional ... icrometer/

viewtopic.php?f=53&t=9214&p=43456&hilit=plastigauge#p43456
http://video.answers.com/engine-bearing ... s-39414874

http://www.summitracing.com/parts/MEL-10990/?rtype=4

http://www.engineparts.com/techbulletin ... 1-205R.pdf

http://www.stealth316.com/misc/clevite- ... ooving.pdf



http://www.circletrack.com/enginetech/c ... ce_basics/



http://garage.grumpysperformance.co...l-pressure-switch-on-fuel-pump-circuit.16013/

http://www.vsihp.com/library/CleviteEng ... sGuide.pdf

http://www.bracketracer.com/engine/mains/mains.htm
http://cleviteonengine.com/askclevite.asp

http://www.jegs.com/p/Clevite/Clevite-7 ... 4/10002/-1

http://ecatalog.mitutoyo.com/Holtest-Ty ... C1530.aspx

Rod bearings 0.002 - 0.025" , side clearance 0.010 - 0.020"

Main bearings 0.002 - 0.003" for most engines ( 0.020-0.025 bearing clearance on small blocks, .025-.027 bearing clearance is about ideal, on big blocks ), 0.005 - 0.007 crankshaft end play

Stock Bearing Clearances

The general rule of thumb for bearing clearances is 0.0010 inch for every 1 inch of journal diameter. That's true for mains and rods, and applies to almost all engines. For the small-block's 2-inch rod journals, that means 0.002 inch of clearance between the rod journal and bearing, by the rule of thumb. The GM-specified tolerances are 0.002 to 0.0025 inch, which lines up well with the rule. Side clearances come in at 0.010 to 0.020 inch, as specified by GM. The clearance rule applies to most engines, but it's generally best to avoid going below 0.0020 inch on any bearing, regardless of the journal diameter.

YOU ALSO HAVE THE OPTION OF HAVING THE CRANK JOURNALS MICRO POLISHED WHILE REMOVING JUST ENOUGH SURFACE FROM THOSE JOURNALS TO GAIN THE REQUIRED CLEARANCE, IF THE CLEARANCE IS TOO TIGHT



http://garage.grumpysperformance.com/index.php?threads/precision-measuring-tools.1390/#post-68861

WATCH VIDEO most larger machine shops can do that cheaply and gain you the required clearance

Influence of Grooved Main Bearings on Performance


Manufacturers are frequently asked what difference grooving makes. Various forms of main bearing grooving have been used over the years.


It’s essential to understand that bearings depend on a film of oil to keep them separated from the shaft surface. This oil film is developed by shaft rotation. As the shaft rotates it pulls oil into the loaded area of the bearing and rides up on this film much like a tire hydroplaning on wet pavement.

Grooving in a bearing acts like tread in a tire to break up the oil film. While you want your tires to grip the road, you don’t want your bearings to grip the shaft, so grooving is bad for maintaining an oil film. The primary reason for having any grooving in a main bearing is to provide oil to the connecting rods. Without rod bearings to feed, a simple oil hole would be sufficient to lubricate a main bearing.

Many early engines used full grooved bearings and some even used multiple grooves. Those choices were based on what engineers knew at the time. As engine and bearing technology developed, the negative effect of grooving was recognized and bearing grooving was removed from modern lower main bearings. The result is in a thicker film of oil for the shaft to ride on.

This provides a greater safety margin and improved bearing life. Upper main shells, which see lower loads than the lowers, and hence don’t apply the same load to the oil film, have retained a groove to supply the connecting rods with oil.

In an effort to develop the best possible main bearing designs for high performance engines, manufacturers have investigated the effects of main bearing grooving on bearing performance. The graphs (Figure 1) illustrate that a simple 180° groove in the upper main shell is still the best overall design.

While a slightly shorter groove of 140° provides a marginal gain, most of the benefit is to the upper shell, which doesn’t need improvement. On the other hand, extending the groove into the lower half, even as little as 20° at each parting line (220° in total), takes away from upper bearing performance without providing any benefit to the lower half. It’s also interesting to note that as groove length increases so does horsepower loss and peak oil film pressure, which is transmitted directly to the bearing.

Notes: You will still find some full-grooved main sets offered for older engines where demand is low and the engineering cost to bring the sets to current standards is not warranted (bearings generally represent the technology of the time the engine was developed).

http://www.stockcarracing.com/techartic ... ewall.html

http://www.goodson.com/store/template/p ... f3f1075a76

http://www.chevyhiperformance.com/tech/ ... index.html

http://www.circletrack.com/tipstricks/4 ... index.html

http://www.carcraft.com/techarticles/cc ... _tips.html



http://www.hotrod.com/techarticles/engi ... index.html

http://www.engineparts.com/techbulletin ... 1-205R.pdf

http://www.engineersedge.com/lubrication/molybdenum_disulfide_characteristics.htm

when assembling any engines valve train component parts and bearing surfaces,should be carefully cleaned and soaked with moly spray and then coated with moly assembly lube prior to assembly, Moly exists as microscopic hexagonal crystal platelets Several molecules make up one of these platelets. A single molecule of Moly contains two sulfur atoms and one molybdenum atom. Moly platelets are attracted to metal surfaces. This attraction and the force of moving engine parts rubbing across one another provide the necessary thermochemical reaction necessary for Moly to form an overlapping protective coating like armor on all of your engine parts. This protective armor coating has a number of properties that are very beneficial for your engine.

The Moly platelets that make up the protective layers on your engine surfaces slide across one another very easily. Instead of metal rubbing against metal, you have Moly platelets moving across one another protecting and lubricating the metal engine parts.

This coating effectively fills in the microscopic pores that cover the surface of all engine parts, making them smoother. This feature is important in providing an effective seal on the combustion chamber. By filling in the craters and pores Moly improves this seal allowing for more efficient combustion and engine performance.

This overlapping coating of Moly also gives protection against loading (perpendicular) forces. These forces occur on the bearings, and lifters. The high pressures that occur between these moving parts tend to squeeze normal lubricants out.

http://www.carbideselect.com/burshpescuts.php
Ive generally found the H-series bearings are the best choice, remember most after market cranks have beveled crank journals requiring matched beveled edge (H) style bearing inserts, standard bearings will have the edge of the bearing insert bind on the radias edge

in a properly set up block a pressurized oil film supports the cam and main bearings
http://carcraft.automotive.com/66890/cc ... -tips.html

bearings AND connecting rods have an inner facing side and outer side the inner side facing the matching rod has far less edge clearance because they don,t need the radias that is required for the edge of the crank journals
IVE dunked my piston/ring assembly's in a can of MARVEL MYSTERY OIL just before installation with a ring compressor and have never seen the slightest indication of problems either on ring sealing getting the rings broken in, or on tearing the engines down later for inspections the amounts not that great, ideally each one installed adds a bit of resistance but at no time should the short block take over 40 ft lbs ABSOLUTE MAXIMUM to start it spinning,and LESS than 20 lbs to keep it moving, even with all the rings and pistons installed,yes you need to verify the bearing clearances during assembly and IT SHOULD take between 20lbs-25 lbs to start it spinning if the clearances are correct! and LESS than 20 lbs to keep it moving
IF it takes over 40 ft lbs to get it rotating ,youll need too DISASSEMBLE and FIND OUT WHY!
http://www.engineprofessional.com/TB/EPQ410_10-18.pdf

when you get the crank polished take the time and effort to clean out any cross drill oil feed passages and to very carefully de-burr the passage opening edges, as this is a very commonly overlooked issue, below is what at first looks like a perfectly polished crank, with oil feed passages to the rod bearings, but the deep scratches the oil feed passage openings left in the rod bearing surfaces bare witness, after a single rotation, during a trial assembly show they are HARDLY burr free or ready for use, and obviously he failed to check each rod bearing during the assembly process, and probably ignored , what was very likely un-even or rather excessive resistance to the crank rotation. which should never exceed about 40 ft lbs even with all 8 rod bearings and pistons installed

having the correct bearing clearances are critical, to durability, generally you'll want no less than .0022-.0025 with .0025-.0028 preferred for most performance use. I prefer .0025-.0028 most of the time
Both rods & mains.
Bearing Tips And Tricks
1. Always check your micrometer with a standard before measuring.

2. Always use the same micrometer for the journals and to set the inside mic diameter.

3. Torque the rods and mains to spec before measuring a bearing inside diameter.

4. Changing rod bolts or moving from bolts to studs in the main caps will affect bearing clearance.

5. Temperature will affect the accuracy of the micrometer and the size of journal diameters both inside and out.

6. If you have one tight and one loose rod-bearing combination, try switching the bearings between the two. We've seen this work several times when the clearances are just a little bit off.

7. Never mix different bearing families when customizing bearing clearance. If you are using Federal-Mogul coated bearings, don't mix in a half shell uncoated race bearing.

http://www.robertpowersmotorsports.com/Tech2.html

http://www.stockcarracing.com/techartic ... index.html

http://mechdb.com/index.php/Plastigagin ... clearances

from chevy high performance mag
MORE USEFUL INFO

BE 100% SURE that the oil pump bolt or STUD doesn,t protrude past the inner main cap surface , because if it bears on the rear main bearing shell it will almost always result in a quickly failed rear bearing

failure to use the correct stud, bolt or nut or check clearances when mounting an oil pump can cause problems

ONE RATHER COMMON MISTAKE IS USING THE WRONG OIL PUMP STUD OR BOLT TO MOUNT THE OIL PUMP AS IF EITHER EXTENDS THRU THE REAR MAIN CAP IT CAN AND WILL BIND ON THE BEARING AND LOCK OR RESTRICT, SMOOTH ROTATION

watch this video
http://www.summitracing.com/parts/MEL-10778/?rtype=4

use plasti-gauge across the whole bearing as you can have a tapered journal that's correct in one area but loose or tight else-ware

GROOVE the edge of the bearing in the area marked in green as it provides extra lubrication to the bearing where its needed most(the rear support face) that resists the pressure from the clutch and or/torque converter
notice the bearing wears near the edge during the test fit indicating either the bearing is tapered or the bearing or main caps not seated correctly, in any case stop and find out whats causing the problem

http://www.4secondsflat.com/Thrust_bearing_failures.html

http://garage.grumpysperformance.com/index.php?threads/thrust-bearing-wear.619/

http://garage.grumpysperformance.com/index.php?threads/precision-measuring-tools.1390/#post-68861

failure to clean out the oil passages in the block and crank journal cross feed oil holes, resulted in trapped debris being flushed out and scoring the bearings during the test fit process in these bearings, an easily avoided but very common screw-up after a cam or bearing fails and your forced to do a ring, cam,lifter, and bearing replacement
just keep in mind that you'll need to very carefully blend and smooth and carefully clean,the edges of the beveled area where the oil port feeds the bearing surface with some 600 grit sand paper so the oil flows well and theres no edges to cause bearing wear issues or crud left from the process that would get embedded in the bearings.

watch this video
http://www.youtube.com/watch?feature=pl ... dEFGJqpCMY

http://www.jensenhealey.com/tech/plasti ... gauge.html

Rod bearings 0.002 - 0.025" , side clearance 0.010 - 0.020"

Main bearings 0.002 - 0.003" for most engines ( 0.020-0.025 bearing clearance on small blocks, .025-.027 bearing clearance is about ideal, on big blocks ), 0.005 - 0.007 crankshaft end play

Piston to head clearance 0.038 MINIMUM including gasket (.038-.042 quench is what you want with steel rods)(steel rods), 0.060" MINIMUM quench aluminum rods

Valve to piston clearance MINIMUM 0.100" exhaust , 0.080" intake NO VALVE FLOAT
Recommended: 0.080 intake, 0.100 Exhaust (steel rods) 0.100 intake, 0.120 Exhaust aluminum rods
TORQUE SPECS CAN BE FOUND HERE IN THIS LINK
viewtopic.php?f=50&t=1222

re- check with plasti-gauge during the pre assembly
don,t assume the bearing journal diameters are correct, on any crankshaft,
, ( while they are almost certainly correct on a SCAT crank)
its good practice and certainly smart to measure carefully to be 100% sure, and that youve purchased and matched them to the correct matched bearing set!

btw spray the bearing and the crank surfaces, and the plasti-gauge with WD40 before you measure clearances and it won,t tend to stick as much

http://www.goodson.com/store/template/p ... f3f1075a76
Clevite H-Series main bearings were developed primarily for NASCAR racing, but are well suited to other types of competition engines as well. They're especially good for engines that run at medium-to-high revs. They have steel backings with carefully selected overlays and a high crush factor, plus a medium level of eccentricity. H-Series bearings have enlarged chamfers at the sides for greater crank-fillet clearance and are made without flash plating for better seating. They're also available with either 180 degree or 360 degree oil grooves, as well as an extra 0.001 in. of clearance. the 180 degree groove bearing with only the top 1/2 groove in the block is preferred as having the lower 1/2 in the main cap without the groove, has a higher load capacity

LOOK CLOSELY the upper main bearing, that seats in the block, is grooved the lower half that seats in the main cap is NOT GROOVED


HERES A GREAT DEAL OF INTERESTING RELATED INFO

http://garage.grumpysperformance.com/index.php?threads/main-cap-fit-in-block.5945/#post-18302

http://garage.grumpysperformance.com/index.php?threads/splayed-main-caps.1014/#post-3831

http://garage.grumpysperformance.co...block-cylinder-wall-thickness.976/#post-22976

Plastic gauge?

Question: Can plastic gauge read correctly if used on a crank already oiled or with assembly lube?? I am wanting to confirm the work done by my machine shop but I do not want to tear it down and dry it off, just see if they did the clearances correctly. I figure to check one or two main caps...

garage.grumpysperformance.com

http://garage.grumpysperformance.com/index.php?threads/sbc-spacer-bearings.3058/



http://www.stealth316.com/misc/clevite-77-rod-main-bearings.pdf



http://garage.grumpysperformance.co...guess-on-clearances-and-journal-surface.9955/

http://garage.grumpysperformance.com/index.php?threads/thrust-bearing-wear.619/



http://engineparts.com/techbulletins/CL77-1-205R.pdf

http://www.stealth316.com/misc/clevite-77-rod-main-bearings.pdf

http://garage.grumpysperformance.com/index.php?threads/can-i-get-it-polished.9214/#post-43456

 

[IBob]

Do you consider a rod vise necessary for torquing rods to measure inside bearing size or would a couple pieces of 1/4-1/2" thick aluminum in a bench vise be ok?

 

[grumpyvette]

the large shop bench vise works ok,
Ive used two 6" x 3" sections of hard plastic cut from a cutting board, you can buy at most large department stores for under $12 to pad the vise jaws
and protect and support the rods, while I do minor clearance checks and polish work, for several years,
but keep in mind I generally don,t use anything but the cap screw rod designs with full float piston pins in most engines I build, like these top two pictures below as it costs more and takes longer to polish and re-size stock rods, and you find you spend a great deal of effort on inferior rods compared to the SCAT,EAGLE, OLIVER, CROWER, or even SUMMIT RODS THAT CAN BE 200% or MORE stronger and cost in the $300-$500 range , you might be amazed at the deals available at times, Ive purchased OLIVER connecting rods off Craigs list for $250 a set new in the box from guys who are getting out of racing, divorced etc.

yes I use both micrometers and snap gauges and cross check with plasti-gauge
and yes when you compare the crushed width of the plasti-gauge youll find it rarely falls as an exact match to the bar chart tape that is packaged with it so you can judge clearance based on crush width
http://garage.grumpysperformance.com/index.php?threads/bearing-clearances.2726/

one of these board can be cut to form really great jaw pads on a clamp or rod vise

http://www.google.com/products/catalog? ... JsBEPICMAU

http://www.tapplastics.com/shop/product ... 5278680425

http://www.butcher-packer.com/index.php ... 4fd5491929

but very seldom

http://www.kmart.com/shc/s/p_10151_1010 ... 926x00003a

http://www.summitracing.com/parts/SME-906006/

http://www.summitracing.com/parts/PRO-66769/

and while rod vises are not all that expensive they don,t get used all that frequently unless you deal with stock style rods

read this

http://garage.grumpysperformance.co...tion-of-crank-durring-short-blk-assembly.852/

http://garage.grumpysperformance.co...g-and-installing-connecting-rods-pistons.247/

http://garage.grumpysperformance.com/index.php?threads/maximizing-piston-to-bore-ring-seal.3897/

http://garage.grumpysperformance.co...ng-and-basic-piston-ring-info-youll-need.509/

http://garage.grumpysperformance.co...bearing-studs-torque-stretch.9409/#post-34247

http://garage.grumpysperformance.com/index.php?threads/splayed-main-caps.1014/#post-12226

http://garage.grumpysperformance.com/index.php?threads/main-cap-fit-in-block.5945/#post-51651

http://www.grumpysperformance.com/sept2017/1310.jpg

http://www.grumpysperformance.com/sept2017/1311.jpg

http://www.grumpysperformance.com/sept2017/1312.jpg

http://www.grumpysperformance.com/sept2017/1313.jpg

http://www.grumpysperformance.com/sept2017/1314.jpg

 

[IBob]

Thank you, Sir.

 

[grumpyvette]

yes controling heat is a very significant issue but,
maintaining a pressurized hydraulic film of lubricating oil between the moving surfaces is critical, for durability.
honestly the engines lube system is critical to long term durability, and you really can,t reasonably expect an engine to last if you don,t maintain consistent cooling and lubrication.

http://www.grumpysperformance.com/july2017/bearingh1.jpg

http://www.grumpysperformance.com/july2017/bearingh2.jpg

http://www.grumpysperformance.com/july2017/bearingh3.jpg

http://www.grumpysperformance.com/july2017/bearingh4.jpg

http://www.grumpysperformance.com/july2017/bearingh5.jpg

http://www.grumpysperformance.com/july2017/bearingh6.jpg

http://www.grumpysperformance.com/july2017/bearingh7.jpg

http://www.grumpysperformance.com/july2017/bearingh8.jpg

http://www.grumpysperformance.com/july2017/bearingh9.jpg

http://www.grumpysperformance.com/july2017/bearingh10.jpg

http://www.grumpysperformance.com/july2017/bearingh11.jpg

http://www.grumpysperformance.com/july2017/bearingh12.jpg

http://www.grumpysperformance.com/july2017/bearingh13.jpg

yes controlling engine and lubrication oil heat is a very significant issue but,
maintaining a pressurized hydraulic film of lubricating oil between the moving surfaces is critical, for durability.your valve springs won,t last 20 minutes without some cooling oil flow to prevent them from over heating and I can,t believe how many people actually believe a crank shaft journal actually rides directly on the bearing surface , without that pressurized film of oil separating the two moving surfaces the bearings are going to be trashed in minutes

http://garage.grumpysperformance.com/index.php?threads/oil-system-mods-that-help.2187/

http://garage.grumpysperformance.com/index.php?threads/basic-info-on-your-v8-lube-system.52/

http://garage.grumpysperformance.com/index.php?threads/bearings-and-oil-flow.150/

http://garage.grumpysperformance.com/index.php?threads/oil-accumulator.1280/

http://garage.grumpysperformance.co...te-filter-require-a-new-pump.3144/#post-62980

http://garage.grumpysperformance.co...l-cooler-increases-durability.176/#post-48374

http://garage.grumpysperformance.co...y-in-building-a-good-engine.11682/#post-54682

http://forum.grumpysperformance.com/viewtopic.php?f=54&t=3536&p=9372#p9372

http://garage.grumpysperformance.co...g-up-oil-feed-holes-in-bearings-shells.10750/

http://garage.grumpysperformance.co...ng-clearances-engine-builders-magazine.11965/

http://garage.grumpysperformance.com/index.php?threads/valve-spring-cooling-via-engine-oil.6491/

http://garage.grumpysperformance.co...oil-passages-and-improved-oil-flow-mods.3834/

http://garage.grumpysperformance.co...m-sure-your-convinced-its-the-oil-pump.11085/

http://garage.grumpysperformance.com/index.php?threads/reducing-friction-and-pumping-losses.8966/

http://mahleclevite.com/publications/EB-10-07.pdf

For technical service call:
1-800-248-9606

CLEVITE CATALOG

http://www.kingbearings.com/ecatalog.php

KING BEARINGS

http://www.grumpysperformance.com/bearinghh4.jpg[/img
http://www.grumpysperformance.com/bearinghh5.jpg
http://www.grumpysperformance.com/bearinghh6.jpg

http://www.grumpysperformance.com/plas5va.jpg
http://www.grumpysperformance.com/1310.jpg

Even with roller valve train there is a break in period where the metals have to "mate". on flat tappet valve trains and non-roller rocker valve trains use of a good moly assembly lube is critical, Break in oils and assembly lubes have high pressure additives to help protect these new surfaces while this "mating" is taking place. Regular motor oil does not, always have the required additives or enough of them. thus using a good moly based assembly lube on lifters and bearings helps reduce wear , on roller rockers and roller lifter a mix of 50% assembly lube and 50% MARVEL MYSTERY OIL, thins this moly mix viscosity allowing it to penetrate roller bearings far faster

http://www.grumpysperformance.com/crcassembly.jpg

http://www.grumpysperformance.com/marvel.jpg

don,t forget to verify the cam to connecting rod clearances
a cams VALVE LIFT is determined by the DISTANCE the lifter moves as the cam rotates under the lifter base as it moves from the cam lobe base circle
(the closest the lifter comes to the cams center line)
up to the cam lobes ramp to the lobes peak,
(the furthest the lifter up off or from the cams center line)


your cams lift, is the result of the lifter movement, or distance it travels from the cams base circle, where the valves seated, to the point in the cams rotation where the lifters moved along the ramp surface fully up on the nose of the cam lobe where the valves at full lift.
example
lets say in this case we compare two imaginary cams
a standard cams base circle is 1.125" and
your cams running on a .900 base circle
both cams have a .560 valve lift and run with 1.5:1 rockers
so both cams will need to move the lifter .374"
that means the standard cam lobe will be 1.125"+.374" or 1.499" from the cams base to the cam lobe nose
that means the small base cam lobe will be .900"+.374" or 1.274" from the cams base to the cam lobe nose
which is significantly smaller,
small base circle cams are generally only used when connecting rod clearance necessitates there use

http://www.grumpysperformance.com/lift&dur.jpg

[IMG]http://www.grumpysperformance.com/baselobeda.jpg

the BASE CIRCLE IS NEVER A CLEARANCE ISSUE, its the cam LOBES that can potentially contact the edge of the connecting rods or bolts, this is why the rods or rod bolts are machined for additional clearance for the cam lobes as you rather obviously CAN,T machine the cam lobes themselves without destroying their function.
now think about it for a few seconds
the cams lobe lift and the cams LSA or LOBE SEPARATION ANGLE
both have an effect on the cam lobes potential interference with the connecting rods

notice how the rod bolts come close to the cam bearings as the pistons reach top dead canter in the bores

RODS WELL AWAY FROM CAM LOBES

RODS CLOSE TO CAM LOBES

WITH THE CORRECT SOFT WARE BOTH THE PISTON TO VALVE CLEARANCE AND CAM TO ROD CLEARANCE CAN BE CALCULATED
BUT ANY COMPETENT ENGINE BUILDER WILL PHYSICALLY VERIFY CLEARANCE

http://garage.grumpysperformance.com/index.php?threads/virtual-dyno-software.2301/#post-53646

http://www.auto-ware.com/software/eap/eap.htm

http://garage.grumpysperformance.co...-bearing-trashed-in-1-2-hour.5141/#post-71921

http://garage.grumpysperformance.com/index.php?threads/thrust-bearing-wear.619/#post-37676

http://garage.grumpysperformance.co...ed-holes-in-bearings-shells.10750/#post-64733

http://garage.grumpysperformance.com/index.php?threads/precision-measuring-tools.1390/#post-52466

 

[grumpyvette]

keep in mind while your assembling the components for your engine that its usually a good idea to buy a complete matched rotating assembly from a single manufacturer, Ive used G.M. forged and SCAT forged components for decades, cast cranks and MANY stock rods are not designed to be used under race stress levels, the OME blocks, are not designed for those stress levels either. its the quality of the machine work and balancing plus attention to details like bearing clearances and the damper used that has a HUGE effect on durability , Ive built dozens of engines with SCAT cranks both CAST STEEL and 4340 FORGED STEEL, with ZERO issues.
the mere fact that there is a problem, encountered with bearing clearances, while checking with micrometers or plastic-gauge, or excess resistance to rotation or a clearance issue found with the rotating assembly components or of needing excess force to spin the engine indicates MAJOR assembly issues, that must be corrected before you proceed further with assembly.
the links posted go into most of the potential things that need to be checked BEFORE, and During the assembly process.
Even a forged 4340 crank will quickly fail if you don,t balance and assemble an engine with those factors set up correctly,and the FACT is that a forged steel or CAST STEEL crank is made of stronger material than a cast iron crank, thats not in dispute, its the engine builder thats responsible to make sure the clearance work, , parts selection,and balance work and parts matching process is correctly completed.
get cheap, assemble a random bunch of miss matched components , forget to do the clearance work, install a damper thats not correct and ANY crank assembly will eventually fail.
theres a reason why a forged crank is usually selected for a race engine, its FAR MORE DURABLE
why cast cranks and high stress and high rpms are a bad idea
and NO! THESE ARE PICTURES OFF THE INTERNET, IVE NEVER BUSTED A CRANK, BUT I AM AWARE IT HAPPENS and TEND TO AVOID USE OF CAST IRON CRANKS, OR STOCK CONNECTING RODS IN RACE APPLICATIONS

RELATED INFO

viewtopic.php?f=53&t=852

viewtopic.php?f=53&t=204

viewtopic.php?f=53&t=852

viewtopic.php?f=53&t=247

viewtopic.php?f=53&t=2726

viewtopic.php?f=52&t=399

viewtopic.php?f=52&t=181

viewtopic.php?f=53&t=3554

viewtopic.php?f=53&t=341

viewtopic.php?f=44&t=38

viewtopic.php?f=69&t=5123

 

[grumpyvette]

"hey grumpy?
The machine shopI used said the crank I brought them, needed to be turned down and re-polished, the guy who turned the crank said they turned it 10/10, so I bought 10/10 bearings. BUT The crank was already 10/10,when I bought it, the shop didn't mean to say it was an additional .010, do you think?, well I assembled the engine and Ive got 5PSI at idle and only 7 psi once its up at 2000rpm so I shut it off and checked, the rods seem to have a good deal of side too side clearance,now what?"


your certainly NOT the first guy to take a machine shops word on the bearing clearances, only to find out that your info was either WRONG or you miss-understood what was said, thats why YOU MUST check each and every bearing clearance, rod side clearance, valve train clearance, rotating assembly and oil pump clearance, deck clearance, ETC.! and rocker geometry measurement in the engine during the assembly process.
I know several guys that took a machine shops "WORD" as the truth on machine work BEFORE they had problems, who will NEVER AGAIN assume machine shops do things correctly, I know I got screwed a couple times by machine shops when I was much younger, before I learned that PEOPLE MAKE MISTAKES and MANY MACHINE SHOP PERSONNEL, just don,t do quality work, so your forced to verify clearance yourself

heres some threads youll want to read thru before re-assembly...
yes it could take you all day to read these threads and sub links,
but it could save you hundreds of dollars and a bunch of cash,
so its well worth the effort


viewtopic.php?f=53&t=852

viewtopic.php?f=53&t=5478

viewtopic.php?f=53&t=247

viewtopic.php?f=53&t=6926

viewtopic.php?f=53&t=6352

viewtopic.php?f=53&t=619

viewtopic.php?f=53&t=509

viewtopic.php?f=53&t=4419

viewtopic.php?f=53&t=3449

viewtopic.php?f=53&t=1478

viewtopic.php?f=54&t=1800

viewtopic.php?f=53&t=1138

viewtopic.php?f=50&t=7604&p=25728&hilit=side+clearance#p25728

viewtopic.php?f=50&t=4946&p=13685&hilit=plastigauge#p13685

 

[grumpyvette]

heres a few links worth reading thru

MEASURE CAREFULLY

When refinished, the surface of a crankshaft will develop microscopic peaks which are “tipped” in the direction that the sparks spray during grinding (see the illustration above). If these peaks point toward the oil film area when the engine is running, lubrication is interrupted, and the bearing will show premature wear. It is important that the crankshaft be ground and final polished so that these peaks are tipped opposite the direction that the crank rotates when it is installed in the engine, this is referred to as the “favorable” direction. We recommend grinding the crank in the “favorable” direction, followed by a multi-step polishing process using progressively finer paper. The first polishing operation uses 280 grit paper with the shaft rotating in the reverse direction – this helps to “knock off” some of the raised material left over from grinding. The second polishing process uses 320 grit paper, and the crank should be rotating in the “favorable” direction. A third step polish with a very fine (400 grit) paper is optional, but should again be done in the “favorable” direction. If the thrust surface was contacted during the resizing operation it must also be polished.

HERES WHAT A MACHINE SHOP CRANK POLISHING BELT LOOKS LIKE

care must be taken to ensure the journal does not get polished unevenly, tapered or egg shaped

journal surface must be polished so micro burrs face away from the direction of rotation on bearing surface for max durability on bearing surface, burrs far to small too see or feel still induce wear

http://www.kingbearings.com/files/Engin ... d_Them.pdf

http://www.kingbearings.com/files/Engin ... y_Work.pdf

http://www.kingbearings.com/files/Geome ... arings.pdf

 

[grumpyvette]

"grumpy do you bother to dunk the piston in oil or do you just oil the rings before installing pistons in the block?"

read thru these links theres a bit more involved that stuffing a well oiled piston in the block.
http://forum.grumpysperformance.com/viewtopic.php?f=53&t=852

http://forum.grumpysperformance.com/viewtopic.php?f=53&t=247

http://forum.grumpysperformance.com/viewtopic.php?f=53&t=4630

http://forum.grumpysperformance.com/viewtopic.php?f=53&t=509

http://forum.grumpysperformance.com/viewtopic.php?f=53&t=3897&p=10316&hilit=ring+compressor#p10316

Influence of Grooved Main Bearings on Performance
http://www.enginebuildermag.com/Article ... mance.aspx

Manufacturers are frequently asked what difference grooving makes. Various forms of main bearing grooving have been used over the years.


It’s essential to understand that bearings depend on a film of oil to keep them separated from the shaft surface. This oil film is developed by shaft rotation. As the shaft rotates it pulls oil into the loaded area of the bearing and rides up on this film much like a tire hydroplaning on wet pavement.

Grooving in a bearing acts like tread in a tire to break up the oil film. While you want your tires to grip the road, you don’t want your bearings to grip the shaft, so grooving is bad for maintaining an oil film. The primary reason for having any grooving in a main bearing is to provide oil to the connecting rods. Without rod bearings to feed, a simple oil hole would be sufficient to lubricate a main bearing.

Many early engines used full grooved bearings and some even used multiple grooves. Those choices were based on what engineers knew at the time. As engine and bearing technology developed, the negative effect of grooving was recognized and bearing grooving was removed from modern lower main bearings. The result is in a thicker film of oil for the shaft to ride on.

This provides a greater safety margin and improved bearing life. Upper main shells, which see lower loads than the lowers, and hence don’t apply the same load to the oil film, have retained a groove to supply the connecting rods with oil.

In an effort to develop the best possible main bearing designs for high performance engines, manufacturers have investigated the effects of main bearing grooving on bearing performance. The graphs (Figure 1) illustrate that a simple 180° groove in the upper main shell is still the best overall design.

While a slightly shorter groove of 140° provides a marginal gain, most of the benefit is to the upper shell, which doesn’t need improvement. On the other hand, extending the groove into the lower half, even as little as 20° at each parting line (220° in total), takes away from upper bearing performance without providing any benefit to the lower half. It’s also interesting to note that as groove length increases so does horsepower loss and peak oil film pressure, which is transmitted directly to the bearing.

Notes: You will still find some full-grooved main sets offered for older engines where demand is low and the engineering cost to bring the sets to current standards is not warranted (bearings generally represent the technology of the time the engine was developed).

A FEW VIDEOS TO HELP YOUR ASSEMBLY

http://www.youtube.com/watch?v=eSxjI6BxgpI

http://www.youtube.com/watch?v=PXFT4ShDryk

http://www.youtube.com/watch?v=PbbPXuwDYfE

http://www.youtube.com/watch?v=rXp1vVtsp7s

http://www.youtube.com/watch?v=xQFlaDhWsck

http://www.youtube.com/watch?v=r1PO26ZqUEs

http://www.youtube.com/watch?v=sQhNIiPyTB4

http://www.youtube.com/watch?v=iuj9nfQ-LRY

http://www.youtube.com/watch?v=HrtQVhcTPFc

http://www.youtube.com/watch?v=ypQwgm1H2NU

http://www.youtube.com/watch?v=-VwsbEg7Z4I

http://www.youtube.com/watch?v=bcMuttJ9RFc

http://www.youtube.com/watch?v=1LcYEZwOIQQ

 

[87vette81big]

Grumpy,

Can You give more insight on the Bearing oil running clearance shown above ?
What size or diameter of mains & rods used.
What make of engine ?
What weight of oil used?
Graphs shown do they show entire oil engine flow requirements ?
Or just a Single main bearing journal ?
Read through 1/2 of your links.
Only so much time to read each day lately.
Been non stop busy.
Read & post from my phone when have a few moments.

Pontiac & Olds V8 engines are similar but my different from Chevys in regards to oiling system.
Been a long habit of mine to check & measure all with Calibrated micrometers & Sunnen Dial Bore Gauges.
Set up to .0001 or within 1/10,000 desired main & rod bearing runners oil clearances.
All bearings lap in during break in
I account for extra bearing to crank clearance after break in.

 

[87vette81big]

Thanks Grumpy !

Brian R.

 

[grumpyvette]

as Im sure your aware I take the more interesting or potentially instructive questions I answer on other sires and cut and paste them on this sites to add data to this sites library of useful info.
that question
"grumpy do you bother to dunk the piston in oil or do you just oil the rings before installing pistons in the block?"
came with very little extra info so I answered it as best as I could, below,



read thru these links theres a bit more involved that stuffing a well oiled piston in the block.
http://forum.grumpysperformance.com/viewtopic.php?f=53&t=852

http://forum.grumpysperformance.com/viewtopic.php?f=53&t=247

http://forum.grumpysperformance.com/viewtopic.php?f=53&t=4630

http://forum.grumpysperformance.com/viewtopic.php?f=53&t=509

http://garage.grumpysperformance.com/index.php?threads/crankshaft-journal-surface-finnish.2728/

http://forum.grumpysperformance.com/viewtopic.php?f=53&t=3897&p=10316&hilit=ring+compressor#p10316

 

[bytor]

Huh, this is interesting. I missed this when studying for my build. Don't most small block bearings come with only one half that has the groove in it? It makes since though.

 

[grumpyvette]

http://www.stealth316.com/misc/clevite- ... ooving.pdf

http://stealth316.com/misc/clevite-77-r ... arings.pdf

http://kingbearings.com/files/Engine_Be ... erials.pdf

you might keep in mind bearing manufacturers are in business to sell bearings and if a small but consistent segment insists on buying and paying for 270 and 360 degree bearings the manufacturers will supply that demand to make a profit, they will also post tech bulletins explaining why a 180- degree oil feed groove in only the upper bearing shell provides a more durable bearing that carries more load capacity

heres a quote from a bearing manufacturer
extending the main bearing groove much past 180 degrees increases friction, reduces load capacity costing hp, read the link
"Influence of Grooving on Main Bearing Performance
Various forms of main bearing grooving have been used over the years. We are
frequently asked what difference grooving makes.
First, it’s essential to understand that bearings depend on a film of oil to keep them
separated from the shaft surface. This oil film is developed by shaft rotation. As the shaft
rotates it pulls oil into the loaded area of the bearing and rides up on this film much like a
tire hydroplaning on wet pavement. Grooving in a bearing acts like tread in a tire to break
up the oil film. While you want your tires to grip the road, you don’t want your bearings
to grip the shaft.
The primary reason for having any grooving in a main bearing is to provide oil to the
connecting rods. Without rod bearings to feed, a simple oil hole would be sufficient to
lubricate a main bearing. Many early engines used full grooved bearings and some even
used multiple grooves. As engine and bearing technology developed, bearing grooving
was removed from modern lower main bearings. The result is in a thicker film of oil for
the shaft to ride on. This provides a greater safety margin and improved bearing life.
Upper main shells, which see lower loads than the lowers, have retained a groove to
supply the connecting rods with oil.
In an effort to develop the best possible main bearing designs for High Performance
engines, we’ve investigated the effects of main bearing grooving on bearing performance.
The graphs on the next page illustrate that a simple 180° groove in the upper main shell is
still the best overall design.
While a slightly shorter groove of 140° provides a marginal gain, most of the benefit is to
the upper shell, which doesn’t need improvement. On the other hand, extending the
groove into the lower half, even as little as 20° at each parting line (220° in total), takes
away from upper bearing performance without providing any benefit to the lower half.
It’s also interesting to note that as groove length increases so do Horsepower Loss and
Peak Oil Film Pressure which is transmitted directly to the bearing."

the oil groove terminates before it gets to the bearing parting line. This style of main bearing has accounted for a 15 percent or more increase in hot idle oil pressure. So if you're looking to eliminate some of those unexplained low oil pressure gremlins contact your bearing manufacturer and ask about this style bearing and availability for the engine applications that you are building.

keep in mind only the upper main bearing shell should have an oil groove, having a 360 degree oil groove lowers the bearing ability to handle high rpm loads

THESE BEARING PICTURED ABOVE, LOOK GREAT BUT HAVE LOWER LOAD CAPACITY

a 180 degree bearing has only the upper in the block grooved to improve oil flow,a 270 degree has the oil feed groove extend further 45 degrees on each lower bearing shell

MAIN BEARINGS WITH 360 degree oil grooves

 

[87vette81big]

I prefer Half Grooved Main Bearings too.

When you build a Pontiac 455 or Olds Small Block or 425-455 You have a difficult time finding Half Grooved bearing sets.
Oldsmobile used fully grooved main bearings OEM except in #1 position.
Clevite only sells replacement full grooved main bearings for them.

The Clevite 455 , 421 main bearing sets are not a true half grooved set no longer.
#4 Thrust is now full grooved.
I have collected several NOS early Clevite & Vandervell Pontiac 3 inch & 3-1/4 inch main bearing sets last 5 years. True Half grooved.

They make it much easier for Chevrolet engines.

 

[Indycars]

What good is the world's best oiling system to the MAINS, if the rod bearings fail !

Would it not be a balance between the main and rod bearings, they both have to
survive ??? So the length of the groove would be right, when both main and
rod bearings have equal wear.

 

[87vette81big]

What good is the world's best oiling system to the MAINS, if the rod bearings fail !

Would it not be a balance between the main and rod bearings, they both have to
survive ??? So the length of the groove would be the right, when both main and
rod bearings have equal wear.

True Rick.
The Big Block Chevrolet has one of the best oiling systems.
Aftermarket Dart Little M a near copy cat of BBC in a. SBC.

You venture outside of Chevrolet and work on Oldsmobile, Pontiac, Buick, Mopar small block, 383-440-426 Hemi, Ford 302-460, and others, unique oiling systems on each V8 engine.
Different know how tricks required.

Found a really good article by Joe Mondello back in 2008 .
One of his last before passing on.
Post soon for others to read.
Informative & Joe tells all with experience building engined since 1949.
The year the 303 V8 Rocket came out.

 

[grumpyvette]

http://www.enginebuildermag.com/2012/10 ... -bearings/

Engine bearing design and development have become more important in the quest for increased efficiency and performance. (Photo from ACL)

Engine bearings have a tough job to do for such a small component. They must support big loads on a thin film of oil (between .0001-.0004? thick) between themselves and the crankshaft journals to prevent metal-to-metal contact.

One of the biggest causes of bearing failures is dirt and debris that enters into the oil pan and gets sucked between the bearing surface and the crankshaft, interrupting that thin film of oil, creating a metal-on-metal contact. From that moment, various engine applications and bearing materials may react differently but the end result is usually still the same – a wiped bearing. And no engine builder or bearing manufacturer wants that.

We spoke to bearing manufacturers to find out what direction technology is heading regarding bearing materials and design, as well as how engine builders can better understand which bearings to use in specific applications.

“As engines have developed, ‘design’ and ‘manufacturing’ have become increasingly important terms,” says Mike Scott of ACL Bearings. “This is predominantly driven by the increase in engine efficiencies resulting in higher bearing loads and higher bearing operating temperatures while utilizing lower viscosity lube oils.”

The result, according to Scott, has been generally decreasing oil film thicknesses between journal and bearing. “As minimum oil film thicknesses can be less than .0004?, the shape (design) and manufacturing precision are key to assisting the generation of stable oil films and ensuring shaft-to-bearing separation under all operating conditions,” he explains.

Although quality bearings have inherent properties that compensate for a degree of misalignment (what bearing engineers refer to as conformability) and provide protection from hard contaminants within the oil (embeddability), engine builders can do a lot to ensure bearing durability by paying close attention to crankshaft preparation and overall cleanliness of the build. In fact, a significant percentage of bearing failures can be traced back directly to the assembly process, so it is a good idea to keep it as clean as possible.

“What is most important for installers is cleanliness in the assembly,” says Federal Mogul’s Bob Sturk. “Everything must be as spotless as possible. Dirt is the number one killer of bearings. When we have failures it’s always, by a vast majority, from debris and embedded dirt.
Echoing Sturk’s cleanliness comments, MAHLE Clevite’s Brett Dayringer says that thoroughly cleaning the block after machining is the best way to prevent dirt and debris getting into the oil system after a rebuild.

“Using hot soapy water and a good selection of bristle brushes is the best method for cleaning cylinder blocks, crankshafts and other engine parts before reassembling the engine,” says Dayringer. “Remember, any debris remaining after a rebuild will be picked up by the oil system and make its way to the bearings.”

Another important consideration when working with your engine bearings to pay attention to is that the wall sizes are consistent so that you can set the clearances without having to go through and measure several bearings for the right fit.

From a manufacturer’s perspective, King’s Ron Sledge says they recognize that bearing sizes and application-matched materials are very important to the installer and end user. “The installer wants very consistent bearing wall sizes to easily zero in on his desired clearance,” says Sledge. “His cranks are supplied with a consistent size, so he wants the bearings to measure consistently also. He can also save time and money not having to measure different bearing shells to get the correct one to achieve his clearance.”

ACL’s Scott says that his company’s solution, similar to King’s, has been to enhance their precision in the manufacturing process. “We have a portfolio of bearing materials with proven robustness across the range of engine applications,” he says.

Scott continues, “This provides the engine builder with the basic confidence of operating capability. The enhanced precision, particularly over bearing wall thickness, provides additional confidence that optimized bearing clearances will be achieved resulting in: optimized high pressure oil film generation for better load support; increased durability; more predictable oil pressure and flow rates to ensure constant supply throughout the engine; and adequate bearing cooling under all operating conditions.”

Materials Matter

The selection of the right bearing material is vital to a trouble free performance with any application. The most commonly used materials in crankshaft bearings are aluminum, copper, lead and tin. Obviously there are others, say experts, but these are the primary elements that are used. And they are all, on a comparative basis, much softer than the iron and steel crankshafts that run against them.

“Bearing materials are called on to satisfy many different conditions in the engine including load, embeddability and seizure resistance, just to name a few obstacles that they must overcome,” says Sledge.

Luckily, say manufacturers, years of research and testing have developed different material solutions for everything from street duty use to ultra high performance to optimize bearing performance in the aftermarket.

As most engine builders know, modern engines (late ’90s and newer) use bi-metal aluminum bearings, but each manufacturer has its own recipe for the construction and characteristics they are looking for. The basic construction is a steel back with a layer of silicone-aluminum facing the crankshaft.

If you are doing a stock rebuild, Federal-Mogul’s Matt Barkhaus says that it is very simple to choose the right bearing from the catalog, which will list all the specs and various sizes available.

Barkhaus says that on their bi-metal bearings the IDs are bored so the debris is flushed out instead of being embedded. “That’s one of the real benefits of it,” he says. “The other benefit of bi-metal is the wearability. They will last virtually forever, as long as you keep the oil changed and the engine is run in a fairly normal operating condition.”

Aluminum bearings can last much longer in mild load applications because of the wearability and the hardness of the silicon composite that actually polishes the crankshaft and wipes any nodes or debris out of the way or flushes it out, Barkhaus continues.

“OEMs have moved to bi-metal bearings because they are lead-free, economical to manufacture, and are extremely hard, which allows them to perform a very long time in passenger car applications,” says MAHLE Clevite’s Dayringer. “As we’ve all seen, it is not uncommon for modern engines to run 150,000 miles or more on the original bearings.”

Virtually all performance bearings today are constructed using a tri-metal construction. Tri-metal bearings have the same steel back as a bi-metal bearing, a copper-lead intermediate layer, and a surface layer of soft material like Babbitt

“Tri-metal bearings work very well on race and performance engines because they are more forgiving, which allows for better embeddability than a harder bi-metal bearing,” says Dayringer.

Bearing materials are, in some ways, the hidden secret of bearing design, according to our experts. The “hidden” aspect of bearing material capability is in the design of the metallurgical properties embodied in the alloys. So, while all tri-metals and all bi-metals might look alike their properties and abilities can be significantly different.

“While proper fitment provides the basis for bearing system operation the materials provide the basis for system durability,” says ACL’s Scott. “To operate successfully, bearings require a range of attributes that, in terms of material properties, require a degree of compromise. For instance, the strength required to transmit high cyclic loads has to be moderated in order to provide good seizure resistance. How this balance is achieved is different for each bearing’s material/alloy combination. The clearest example is the comparison of properties between aluminum base ‘bi-metals’ and copper-lead based ‘tri-metals.’”

What are the primary differences in hardness, strength and embeddability between today’s aluminum and tri-metal bearings?

“Generally aluminum bearings offer greater embeddability and conformability while tri-metal bearings offer greater fatigue strength and hardness,” says Sledge. “The aluminum alloy layer on top of a steel back is a minimum .012? thick and can embed particles larger than .0005? in dia. The overlay thickness on tri-metal bearings range from .0005?-.0008? therefore allowing less embeddability.”

Federal-Mogul’s Sturk says there are basic differences in the hardnesses of the two bearings as well as some other differences in strength and embeddability. “In my view, embeddability isn’t really that big of a problem. I think today’s aluminum bi-metal bearings can handle a reasonable amount of debris. But if there are excessive amounts, that’s where the tri-metal bearings are better. The over-plate embeddability allows them to handle debris a bit better. If it’s a reasonable amount, if oil has been properly maintained, I don’t really worry about the aluminum’s embeddability.”

If you are looking to extract more power, experts say the copper/lead bearings are likely the optimal choice. Sturk explains that bearing engineers are primarily concerned with unit load as opposed to horsepower numbers in order to rate the strength of a specific bearing or material. Unit loads come from the cylinder pressures that are developed above the bearings in the combustion chamber.

It’s hard for an engine builder to estimate combustion pressure without a lot of expensive testing equipment that an OEM or bearing manufacturer would have, so Sturk says it’s probably best to go with a tri-metal bearing for any upgrade, just to be safe.

There is just a big difference in the wear rates of the copper/lead trimetals and aluminum bimetal bearings, say experts.

The copper lead tri-metal bearings are still the strongest materials available today, says Sturk. He says if you are upgrading or adding a supercharger or using other methods to extract more horsepower, it usually puts higher loads on the bearings. “In that case,” he says, “the tri-metal bearings will handle much higher loads. Our H14 materials (copper/lead) will handle unit loads up around 15,000 psi. The aluminum will handle much less, around 8,000-9,000 psi. It’s a big difference in strength characteristics,” he notes.

According to Dayringer, race and performance engines see more crankshaft deflection, rod housing bore distortion, and thinner oil film thickness compared to passenger car engines and therefore require a different material and construction than bi-metal aluminum bearings. “The softer Babbitt facing allows the bearing face to ‘move’ slightly with the crankshaft to avoid seizure during high load and rpm situations, which makes tri-metal bearings the preferred choice for performance and race engine builds,” he explains.

The attributes that a bearing needs to have can be compared to a tightrope because on the one hand you need hard fatigue strength components for durability and load carrying capacity, but on the other hand you need soft phase characteristics for conformability (when things are out of alignment), embeddability and sliding properties. When manufacturers select a bearing material, they look at the engine application and try to determine the most important thing the engine needs and then design the bearing around that.

Today’s bimetals contain a mix of other materials such as silicon, which is a hard particle that is added for increased durability. They have tin which is considered a soft face metal that is for the embeddability and conformability aspect, so today’s aluminum bi-metals have alloying elements in them to address those issues. But still, not all alloys are the same.

While all tri-metals and all bi-metals might look alike their properties and abilities can be significantly different. Bearing material capability is in the “hidden” part of the design of the metallurgical properties embodied in the alloys.

“The differences get down to alloy composition, casting conditions, bonding methods and heat treatments for bi-metals,” says Scott. “And for tri-metals, it’s the alloy composition, sinter/casting conditions and electroplating/coating technologies that account for any differences.”

All these factors give the bearing manufacturers a great deal of freedom to tailor materials, and it can be confusing for engine builders trying to understand how appropriate the materials are for their specific application. Because the quality of the material may not be clearly apparent it is also hard for engine builders to make a judgment between competing products.

Different suppliers materials do behave differently, and within each family of materials there is a substantial range of capability. It is nearly impossible for a rebuilder to judge, on face value, how any brand of bearing is going to perform across a broad range of characteristics, so experts say it is best to rely on bearings from reputable, established brands.

When bearings are found to be damaged or show unusual or uneven wear, it typically indicates other problems that need correcting, problems that if left uncorrected may cause the replacement bearings to suffer the same fate.

 

[87vette81big]

I read the article Grumpy.
You would never convince me that Bi metal aluminum face bearings are superior.
Cleavite P or H or V series would be my only picks still.
And Vintage New Old Stock Vandervell Indium Trimetal bearings when found & have plenty for Chevy & Pontiacs bought & put away for my own use.

Every Diesel Truck that can go 300,000 - 900,000 miles brtween overhauls has Trimetal Lead Bearings.
Every GM V6 that blows up / spins Main & Rod bearings Have Bi metal aluminum used.
Like a S10 Blazer 4.3 L V6.

 

[Grumpy]

Ive used the clevite (H) in dozens of engines without any problems , (obviously measure clearances and order the correct bearings

http://www.summitracing.com/search/make/chevrolet/engine-size/5-7l-350/engine-family/chevy-small-block-gen-i?keyword=clevite (h) bearing sets

http://garage.grumpysperformance.com/index.php?threads/bearing-clearances.2726/

http://garage.grumpysperformance.co...tion-of-crank-durring-short-blk-assembly.852/

http://garage.grumpysperformance.co...g-and-installing-connecting-rods-pistons.247/

http://garage.grumpysperformance.co...ng-and-basic-piston-ring-info-youll-need.509/


Clevite CR867HP/standard

Mahle

• Clevite P-Series Main Bearings Main Bearings, P Series, 1/ 2 Groove, Standard Size, Tri Metal, Chevy, Small Block, Set of 5
  (MS909P, M25MS909P)
• Clevite P-Series Main Bearings Main Bearings, P Series, 1/ 2 Groove, .020 in. Undersize, Tri Metal, Chevy, Small Block, Set of 5
  (MS909P20, M25MS909P20)
• Clevite P-Series Main Bearings Main Bearings, P Series, 1/ 2 Groove, .030 in. Undersize, Tri Metal, Chevy, Small Block, Set of 5
  (MS909P30, M25MS909P30)
• Clevite 77 MS909P10 Main Brng Set
  (MS909P10, M25MS909P10)
• Clevite P-Series Main Bearings Main Bearings, P Series, 1/ 2 Groove, .001 in. Undersize, Tri Metal, Chevy, Small Block, Set of 5
  (MS909P1, M25MS909P1)
• Clevite P-Series Main Bearings Main Bearings, P Series, 1/ 2 Groove, .030 in. Undersize, Tri Metal, Chevy, Big Block, Set of 5
  (MS829P30, M25MS829P30)
• Clevite P-Series Main Bearings Main Bearings, P Series, 1/ 2 Groove, Standard Size, Tri Metal, Chevy, Big Block, Set of 5
  (MS829P, M25MS829P)
• Clevite P-Series Main Bearings Main Bearings, P Series, 1/ 2 Groove, .020 in. Undersize, Tri Metal, Chevy, Big Block, Set of 5
  (MS829P20, M25MS829P20)
• Clevite P-Series Main Bearings Main Bearings, P Series, 1/ 2 Groove, .010 in. Undersize, Tri Metal, Chevy, Big Block, Set of 5
  (MS829P10, M25MS829P10)
• Clevite P-Series Main Bearings Main Bearings, P Series, 1/ 2 Groove, .001 in. Undersize, Tri Metal, Chevy, Big Block, Set of 5
  (MS829P1, M25MS829P1)
• Clevite P-Series Main Bearings Main Bearings, P Series, 1/ 2 Groove, .020 in. Undersize, Tri Metal, Chevy, Small Block, Set of 5
  (MS1038P20, M25MS1038P20)
• Clevite P-Series Main Bearings Main Bearings, P Series, 1/ 2 Groove, .010 in. Undersize, Tri Metal, Chevy, Small Block, Set of 5
  (MS1038P10, M25MS1038P10)
• Clevite P-Series Main Bearings Main Bearings, P Series, 1/ 2 Groove, Standard Size, Tri Metal, Chevy, Small Block, Set of 5
  (MS1038P, M25MS1038P)
• Clevite H-Series Main Bearings Main Bearings, H Series, 1/ 2 Groove, Standard Size, Tri Metal, Chevy, Small Block, Set of 5
  (MS1038H, M25MS1038H)
• Clevite H-Series Main Bearings Main Bearings, H Series, 1/ 2 Groove, .010 in. Undersize, Tri Metal, Chevy, Small Block, Set of 5
  (MS1038H10, M25MS1038H10)
• Clevite H-Series Main Bearings Main Bearings, H Series, 1/ 2 Groove, .010 in. Undersize, Tri Metal, Chevy, Big Block, Set of 5
  (MS829H10, M25MS829H10)
• Clevite H-Series Main Bearings Main Bearings, H Series, 1/ 2 Groove, .020 in. Undersize, Tri Metal, Chevy, Big Block, Set of 5
  (MS829H20, M25MS829H20)
• Clevite H-Series Main Bearings Main Bearings, H Series, 1/ 2 Groove, Standard Size, Tri Metal, Chevy, Big Block, Set of 5
  (MS829H, M25MS829H)
• Clevite H-Series Main Bearings Main Bearings, H Series, 1/ 2 Groove, .001 in. Undersize, Tri Metal, Chevy, Big Block, Set of 5
  (MS829H1, M25MS829H1)
• Clevite H-Series Main Bearings Main Bearings, H Series, 1/ 2 Groove, .001 in. Thinner Size, Tri Metal, Chevy, Big Block, Set of 5
  (MS829HX, M25MS829HX)

Sealed Power

• Sealed Power 4400MA Crankshaft Main Bearing Set
  (4400MA, SPW4400MA)
• Sealed Power 4663M10 Crankshaft Main Bearing Set
  (4663M 10, 4663M10, SPW4663M10)
• Sealed Power 4663M Crankshaft Main Bearing Set
  (4663M, SPW4663M)
• Sealed Power 4663M30 Crankshaft Main Bearing
  (4663M30, 4663M 30)
• Sealed Power 4663M1 Crankshaft Main Bearing
  (4663M1, 4663M 1)
• Sealed Power 4400MA10 Crankshaft Main Bearing Main
  (4400MA10, 4400MA 10, SPW4400MA10)
• Sealed Power 4663MA Crankshaft Main Bearing Set
  (4663MA)
• Sealed Power Main Bearing Set 4663M20
  (4663M20, 4663M 20, SPW4663M20)
• Sealed Power 4124MA Crankshaft Main Bearing Set
  (4124MA, SPW4124MA)
• Sealed Power Main Bearing Set 4663M40
  (4663M 40, 4663M40)
• Sealed Power Main Bearing Set 4663M60
  (4663M 60, 4663M60)
• Sealed Power Main Bearing Set 4663MA30
  (4663MA 30, 4663MA30)
• Sealed Power 4663MA10 Crankshaft Main Bearing Set
  (4663MA10, 4663MA 10)
• Sealed Power Main Bearing Set 6688M30
  (6688M 30, 6688M30)
• Sealed Power Main Bearing Set 6688M20
  (6688M20, 6688M 20)
• Sealed Power Engine Bearing 6688M10
  (6688M10, 6688M 10)
• Sealed Power 4400MA20 Crankshaft Main Bearing Main
  (4400MA20, 4400MA 20)
• Sealed Power 4926MA10 Main Bearing Set
  (4926MA 10, 4926MA10)
• Sealed Power Main Bearing Set 4663MA60
  (4663MA 60, 4663MA60)
• Sealed Power Main Bearing Set 4663MA40
  (4663MA40, 4663MA 40)
• Sealed Power Main Bearing Set 4663MA1
  (4663MA1, 4663MA 1)
• Sealed Power Main Bearing Set 4663MA20
  (4663MA 20, 4663MA20)
• Sealed Power Main Bearing Set 4663M2
  (4663M2, 4663M 2)
• Sealed Power Main Bearing Set 7329MA10
  (7329MA10, 7329MA 10)
• Sealed Power Main Bearing Set 4400MA1
  (4400MA1, 4400MA 1)
• Sealed Power Main Bearing Set 4400MA30
  (4400MA 30, 4400MA30)
• Sealed Power Main Bearing Set 4400MA40
  (4400MA40, 4400MA 40)
• Sealed Power Main Bearing Set 7274MA10X20
  (7274MA 10X20, 7274MA10X20)
• Sealed Power Main Bearing Set 7122MA30
  (7122MA 30, 7122MA30)
• Sealed Power Main Bearing Set 7122MA10
  (7122MA10, 7122MA 10)
• Sealed Power Main Bearing Set 7122MA20
  (7122MA20, 7122MA 20)
• Sealed Power 4124MA10 Crankshaft Main Bearing Set
  (4124MA10)
• Sealed Power Main Bearing Set 4124MA20
  (4124MA20)
• Sealed Power Main Bearing Set 4124MA30
  (4124MA30)
• Sealed Power Main Bearing Set 4124MA40
  (4124MA40)
• Sealed Power Main Bearing Set 4124MA60
  (4124MA60)
• Sealed Power Main Bearing Set 4926MA
  (4926MA, S124926MA)
• Sealed Power Main Bearing Set 4926MA20
  (4926MA20)
• Sealed Power Main Bearing Set 4926MA30
  (4926MA30)
• SEALED POWER 136M Crankshaft Main Bearing
  (136M)
• Sealed Power 141M Crankshaft Main Bearing Set
  (141M)
• Sealed Power Main Bearing Set 4663MA2
  (4663MA2, 4663MA 2)
• Sealed Power Main Bearing Set 7329MA20
  (7329MA20, 7329MA 20)
• Sealed Power Main Bearing Set 7329MA30
  (7329MA 30, 7329MA30)
• Sealed Power Main Bearing Set 4400MA2
  (4400MA2, 4400MA 2)
• Sealed Power 4926MA1 Crankshaft Main Bearing Main
  (4926MA 1, 4926MA1)
• SEALED POWER 140M Crankshaft Main Bearing
  (140M)
• Sealed Power Main Bearing Set 140M1
  (140M1)
• Sealed Power Main Bearing Set 140M10
  (140M10)
• Sealed Power Main Bearing Set 140M20
  (140M20)
• SEALED POWER 139M Crankshaft Main Bearing
  (139M)
• Sealed Power Main Bearing Set 139M1
  (139M1)
• Sealed Power Main Bearing Set 139M10
  (139M10)
• Sealed Power Main Bearing Set 139M11
  (139M11)
• Sealed Power Main Bearing Set 139M1X
  (139M1X)
• Sealed Power Main Bearing Set 139M20
  (139M20)
• Sealed Power Main Bearing Set 136M1
  (136M1)
• Sealed Power 136M10 Crankshaft Main Bearing
  (136M10)
• Sealed Power Main Bearing Set 141M1
  (141M1)
• Sealed Power Main Bearing Set 141M10
  (141M10)
• Sealed Power Main Bearing Set 141M1X
  (141M1X)
• SEALED POWER C140M Crankshaft Main Bearing
  (C140M)
• SEALED POWER C139M Crankshaft Main Bearing
  (C139M)
• Sealed Power Main Bearing Set C140M1
  (C140M1)
• Sealed Power Main Bearing Set C140M20
  (C140M20)
• Sealed Power Main Bearing Set C140M1X
  (C140M1X)
• Sealed Power Main Bearing Set C139M1
  (C139M1)
• Sealed Power Main Bearing Set C139M20
  (C139M20)
• Sealed Power Main Bearing Set C139M30
  (C139M30)
• SEALED POWER C141M Crankshaft Main Bearing
  (C141M)
• Sealed Power Main Bearing Set C141M1
  (C141M1)
• Sealed Power Main Bearing Set C141M20
  (C141M20)