IT durability thats KEY in building a good engine

Discussion in 'Tools, Procedures, and Testing trouble shooting' started by Grumpy, Sep 29, 2015.

  1. Grumpy

    Grumpy The Grumpy Grease Monkey Staff Member

    when ever I get into a discussion with many of the guys I build engines for, the younger guys especially seem to be captivated or primarily focused on the concept of having
    " a RADICAL CAM, that rumbles at idle, or the new brand X heads that some magazine is pushing in the latest engine build article"
    you can,t have a race wining combo if its spending a great deal of time in the shop being repaired!

    link too bore vs stroke info on hundreds of engines

    before you spend a good deal of money porting and un-shrouding any iron cylinder heads, keep in mind aluminum heads are easily repaired in a skilled and experienced automotive machine shop thats equipped to do those repairs but damaged iron cylinder heads are either much harder to repair or good door stops


    the best route to take is by joining a local car club and talking to dozens of guys at the local car shows and rod runs and at the local tracks,
    GO TO THE LOCAL TRACK, AND GO TO LOCAL CAR SHOWS<ASK LOTS OF QUESTIONS, TALK TO LOTS OF PEOPLE, you'll eventually find out which machine shops AND BODY SHOPS do quality work and which do sloppy or slipshod work, or take money and never do the work correctly at times.
    ALWAYS stamp your parts with your PH# number or some other ID and take clear detailed pictures and get signed receipts listed parts, dates,costs and expected work to be done and dates due and take a picture of the guy your talking to and get the receipt
    look around the shop! if theres dozens of cars sitting outside , rusting, or stacks of greasy engines you probably don,t want your car joining them.

    Its become almost a totally ignored concept,that the rather seldom mentioned sub systems, that prevent or reduce engine wear,systems that provide cooling, for engine oil, coolant and transmission fluid ,that control oil flow and pressure,and concepts like maintaining consistent effective cooling,or that a high capacity baffled oil pan and windage tray and oil pump design helps maintain,component lubrication,or thermal barrier coatings and proper heat control, are critical to durability, as are proper clearances, and selecting the best quality bearings and fasteners, and a quality valve train,components ,researching and then installing ,proper valve train and connecting rod,optimizing valve train geometry, will reduce stress on the components.
    taking the time to get the rotating assembly low stress balanced , stress risers polished out and carefully verifying all the components are designed to function correctly in nearly the same power band at the same displacement and compression, matched to the correct calculated drive train are absolutely critical to longer term durability!

    its the support sub systems and proper assembly that allow the engine to function, they may not be as glamorous as discussing how your buying the newest selection of cylinder heads and cams but without their proper operation your engine starts breaking parts in minutes.
    put the time and effort required into researching, purchase and installation of the highest QUALITY MATCHED COMPONENTS you can afford!
    While cheat sheets might have frowned upon in your sixth-grade classroom, we strongly encourage them in the garage, shop, or pits. That’s why we’ve put together this list of 13 key performance formulas you should know when building or tuning your street or race vehicle.
    btw if youve managed to blow a head gasket on a 1986-91 TPI corvette with aluminum heads
    the heads and block surfaces must be very carefully examined for damage or warping issues and if found those issues must be corrected, before any new head gaskets installed, over time steam can and will cut grooves in even cast iron blocks and rather easily in softer aluminum.

    many magnets lose their magnetic pull if heated to 200F
    these below won,t

    proper magnets trap metallic debris

    SmCo Samarium Cobalt Disc Magnets

    Samarium Cobalt MAGNETS HELP
    magnets are ceramic and glass hard, don,t try to drill or grind them, as they can shatter
    its not that difficult to remove the oil pan, replace the gasket with a new one piece synthetic one and cure that leak,
    most guys can do that in a single afternoon with the car up on 4 12 ton jack stands rather easily.
    be aware that the crank counter weights rotated to the correct location makes removing the oil pan a bit easier.
    it might be a great opportunity to swap to a higher capacity baffled oil pan.
    7" deep
    6.5" deep

    7" deep

    theres lots of 8" and 8.25" deep corvette oil pans but they don,t last too long with speed bumps and raised manhole cover rims dynamic Comp Ratio.htm

    Racing Carburetor CFM
    Racing Carburetor CFM = RPM x Displacement ÷ 3456 x 1.1
    Note: Summit Racing also offers this CFM Calculator to make the job easier.

    Displacement = .7854 x Bore2 x Stroke x Number of Cylinders

    Correct Compression Ratio (CCR)
    CCR = FCR (Altitude/1,000) x .2
    Note: You can also take this Compression Ratio Calculator tool for a spin.

    Tire Diameter
    Tire Diameter = (MPH x Gear Ratio x 336) ÷ RPM

    Rocker Arm Ratio and Valve Lift
    Gross Valve Lift = Camshaft Lobe Lift x Rocker Arm Ratio

    Horsepower = (RPM x Torque) ÷ 5,252

    Torque = (5,252 x HP) ÷ RPM

    Rod Ratio
    Rod Ratio = Rod Length ÷ Crank Stroke Length

    Average Piston Speed
    Average Piston Speed = Crank Stroke x RPM ÷ 6

    Rear Gear Ratio
    Rear Gear Ratio = (RPM at Finish Line x Tire Diameter) ÷ (MPH x 336)
    Note: You can also save this link to a handy Gear Ratio calculator.

    Volume (CCs) of Deck Clearance
    CCs of Deck Clearance = Bore x Bore x 12.87 x Depth of Deck Clearance

    Volume (CCs) of Head Gasket
    CCs of Head Gasket = Bore x Bore x 12.87 x Thickness of Head Gasket

    Ive never yet had anyone start talking about the killer LUBRICATION or cooling system they want to install, or the need to match the intake manifold design to the cam timing and
    you buy bearings only after carefully inspecting and measuring the bearing journals
    only by having all the dimensions accurately measured and verified can you correctly select matching bearings
    you seldom hear how they select cam specs to maximize cylinder scavenging or how they calculated the best thermal barrier coating for the combustion chamber and piston dome surfaces,or the need for an oil accumulator or the great water pump and 4" thick multi core aluminum radiator they are planing on installing, or the careful selection of matched baffled oil pan, oil pump and windage tray, or how the bearing clearances and journal surface prep were going to be set up to maximize bearing cooling and reduce friction. but its the careful matched selection of and care in assembly, that allows the engine to run for more than a few hours before parts fail.
    Or how they were going to pay a bit more to get the rotating assembly balanced and verified as being accurate to 1/2 a gram vs the two gram balance that they were told it came with.
    yes selecting a matching set of cylinder heads, cam, valve train,the stroker rotating assembly and that great engine block get 90% of your attention, but its the things like ARP main cap studs,getting the H series clevite, bearings correctly fitted and clearanced, carefully honing the bore walls and selecting the best connecting rods and pistons that will make a huge difference in the engines ability to withstand stress
    TECH SUPPORT LINES, before you get over your head ASK QUESTIONS

    look IM surely not trying to stop you from building a nice car but start with some basic skills and knowledge of the basic concepts

    start here

    buy these four books and read thru them then watch the cd a few times


    JOHN LINGENFELTER on modifying small-block chevy engines


    then read thru this carefully

    then once youve got a few basics down proceed slowly and carefully and ask questions

    Performance Products provides award-winning technical support via phone Monday through Friday, 8AM to 5PM CST @ 270 781-9741.

    technical support is availible by phone Monday through Friday 7AM to 5PM CST @
    662 892-1500.


    CROWER cams


    please call us at 479-394-1075 for technical support


    If you need to speak with an Edelbrock technician by phone, please call 1-800-416-8628 from 7:00am to 5:00pm, Monday-Friday, PST.

    Tel: (310) 450-0806
    Fax: (310) 452-3753

    phone: 323.770.0930
    fax: 310.515.5730

    28611 W. Industry Drive
    Valencia, California, USA 91355
    tel: 877-892-8844

    DEMON CARBS (Barry Grant Incorporated)
    Phone: (706) 864-8544
    Fax: (706) 864-2206


    TECH LINE: 915-855-7123

    Shafiroff Race Engines
    Toll Free: 800.295.7142 • Phone: 631.218.7530

    Ohio Crankshaft
    5453 SR 49 S
    Greenville, OH 45331
    Toll Free: 800-333-7113
    Local: 937-548-7113
    Fax: 937-548-4603 (KEVKO OIL PANS)
    915 North Orient Street
    Fairmont, Minnesota 56031
    (507) 238-9633
    (800) 770-3557

    Stef's Performance Products
    693 Cross Street
    Lakewood, NJ. 08701
    Phone ( 732 ) 367- 8700
    fax: (732) 367-8793

    Customer Service: 517-787-8172 ext: 125

    call 203-458-0542, 203-458-0546

    Phone: (805) 577-5950
    Fax: 805-577-7540





    310 370 5501

    Schneider Cams
    (619) 297-0227


    hays clutches

    A few of MY favorite parts sources
    248) 438-6900
    • Siamesed Extra-Thick Cylinder Walls: Resists cracking and improves ring seal (minimum .300'' thick with 4.625'' bore).
    • Scalloped Outer Water Jacket Walls: Improves coolant flow around the cylinder barrels to equalize temperatures.
    • Four-Bolt Main Bearing Caps: In steel or ductile iron have splayed outer bolts for extra strength.
    • Crankshaft Tunnel: Has clearance for a 4.500'' stroke crank with steel rods without grinding.
    • True ''Priority Main'' Oil System: Lubricates the main bearings before the lifters.
    • Oil Filter Pad: Drilled and tapped for an external oil pump.
    • Rear Four-Bolt Cap: Uses standard oil pump and two-piece seal - no adapter required!
    • Lifter Valley Head Stud Bosses: Prevent blown head gaskets between head bolts.
    • External Block Machining: Reduces weight without sacrificing strength.
    • Simplified Install : Fuel pump boss, clutch linkage mounts and side & front motor mounts simplfy installation on any chassis.
    • Dual Oil Pan Bolt Patterns: Fits standard and notched oil pans.
    • Bellhousing Flange and Rear Main Bearing: Reinforced with ribs to resist cracks.
    • Note: Does not include cam bearings, freeze plugs, or dowels
    if your going to use a valve train cooling oil flow to cool the valve springs ,you may want to consider other options like a transmission fluid cooler and an oil accumulator

    I find it rather amazing that many guys (even a few corvette owners) don,t realize that the oil cooler between the block and oil filter does remove a noticeable amount of heat from the engine oil, or that in some cases that they even have an oil cooler factory installed. ITS OIL FLOW that absorbs and initially transfers heat away from the bearings and valve train not coolant.
    my 1985 corvette came with a factory oil cooler, that runs engine coolant through separate but contacting internal passages, this warms the oil faster getting it flowing but tends to reduce the heat engine oil can reach as it absorbs oil heat effectively transferring it too the engine coolant on the car, where its transferred too air flow through the radiator

    you'll need to dissipate the heat that oil flow collects as it runs over the surface of those hot valve springs and a combination of a higher capacity baffled oil pan ,
    and an auxiliary oil cooler to make transferring the absorbed heat load the oil carries away from the upper engine is almost 100% mandatory if your expecting the oil to cool the valve train for very long.
    Id point out that you'll almost certainly want to use an oil cooler that's as large as you have room to effectively use and having a powered fan to increase air flow and heat transfer efficiency will help, bu remember the line size between the engine cooler and back to the engine will generally slightly restrict flow so, I,d advise at least a AN#8 or 1/2" internal cross sectional, size oil or hydraulic lines designed to handle 300F temps and pressure levels with a significant safety margin above what the engine produces, and having large remote mounted oil filter(s) won,t hurt either.
    think about it a bit, the ideal trans coolant temp should be in the 150F-160F range, so how you route the trans fluid cooler lines maters, engine coolant can easily run 210F-230F going into the top of the radiator, from a hot engine and run 170F-180F returning too the engine after its trip through the radiator, thats more likely to heat than cool transmission fluid.
    having an aux trans cooler with an electric powered fan and AN#8 minimum line size is generally a very good idea!(obviously you need to have the clearance and location to mount it

    out of trans, to radiator cooler, out to
    aux cooler, back to trans?

    Yes they make dual transmission fluid and oil coolers so you might want to consider that option if you have an automatic transmission and Id sure suggest a fluid temp gauge that accurately measures transmission fluid and a separated gauge for oil temperatures.
    IM currently using this transmission fluid cooler on my 1985 corvette but have used others in the past, and a dual cooler like this certainly has some advantages , if you need both oil and transmission fluid cooling.
    Adding a high quality transmission and oil cooler with low flow restriction 1/2" MINIMUM ID lines can markedly increase engine longevity and durability
    most hydraulic supply shops will fabricate lines to your exact length and use the correct fittings and hose types to allow over 1000psi and 300F fluid temps, if you do a bit of reserch youll find a couple hydraulic supply shops locally

    this is one reason why combining both the engine oil cooler and transmission fluid cooler in a single dual unit is not always ideal,in every car, as an example on my corvette I found that I did need an oil cooler but did need a trans cooler , because once I installed a custom 10 qt oil pan on my 383 the oil temp stayed in the desired range due to the pans much larger surface area and the and much larger capacity, but the transmission fluid due to the 3200 stall speed converter did need to be cooled
    [​IMG] ... _15721.pdf
    If your going to run an effective oil cooler with a fan you'll generally want a thermostat controlling oil temps to be sure the oils neither too hot or too cold, you'll generally want the oil to rather rapidly heat to a 200F-21fF range during normal operation,to insure its hot enough to boil off moisture , and reduce sludge but run through the cooler to prevent it getting over about 220F where the temp tends to degrade lubrication efficiency

    don,t forget that oil flow rates, and reducing the transmission fluid temp in the lower radiator on cars equipped with an automatic transmission, have a big effect on engine cooling so adding a trans or oil cooler helps engine durability
    posted these diagrams that will be helpful


    [​IMG] `
    When having a machine shop do any work, always ALWAYS get everything in detailed writing before you start,
    specifying all machine work, to be done in detail,list parts and labor costs, mandate a delivery due dates and have every single part you supply ID stamped, and photographed, have all the work too be done and parts individually listed and a value assigned, with both YOU and the machine shop having identical signed copys
    listing the cost and dates and work details


    a few links may help here

    that RUMBLE,in the exhaust note, they all value is mostly the result of low rpm air flow reversion,it takes TIME for airflow to fill a cylinder, and as the rpms increase that time is greatly reduced, at 1000rpm, the cylinder fills and empty's about 8.3 times a second , valve timing, controlled by the cam lobe duration, is generally in the 200 degrees of crank rotation range, but a cam with that limited duration will not allow efficient air flow through the cylinder at higher rpms.
    at 7000rpm your popping those valves open and closed 58 times a second, and cam duration needs to be increased from a stock cams 200 degree duration range to something closer to 265-280 degrees to allow effective air flow, but that also results in both the intake and exhaust valves remaining open for 30-50 degrees at the same time and at lower engine speeds the inertia in the exhaust and intake tracks is rather low resulting in some old exhaust,being pushed back into the cylinder as the piston tries to push out the old spent exhaust gases out the still open exhaust valve while the intake valve is starting to open, this tends to dilute the intake charge, and the engine basically chokes on the fouled mix of UN-ignitable compressed gases


    Id also point out that cam timing matched to the exhaust scavenging has a huge effect on potential intake flow rates

    there seems to be an almost total lack of understanding,of how and why a certain cams matched to other components. radical cams sound the way they do because they are built with longer duration and faster lobe acceleration ramps the increase the speed the valve train operates at per degree of rotation,or increase the lift on a cam lobe ramp per degree of rotation, and this increase in valve speed comes at the expense of what can be greatly increased inertial loads that generally can cause noticeably faster wear , or in some cases almost a designed in impending parts breakage within a very short life span, on the valve train components and at some point, a lack of predictable control over consistent and reliable valve train movement.

    as any engineer will point out as the rpms increase the stress on moving parts increases but the stress is not directly equal to the rpm , IE double the rpm=double the stress, its more like double the rpm and square the stress, plus stress on components is cumulative, push parts to near maximum critical stress levels and eventually they fail, even if they don,t quite push over the original stress fail point.

    a film of warm pressurized oil and assembly lube being constantly pushed to flow over and between the moving components can prevent them from physically wearing each surface, and assembly lube with a moly base can provide a slick low friction surface for the moving components 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.
    but keep in mind that the spring pressures required to maintain valve train control at higher rpms place a significant load on those sliding surfaces.
    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.

    changing the oil filter after an hour or so of run time, and use of several magnets in the engine will reduce the potential for trash in the oil.
    the fact is that many times selecting a slightly milder cam with a bit less lift and more gradual cam lobe acceleration ramp speeds can go a long way toward reducing valve spring failures and increasing valve train stability,yes it might cost you 5-10 peak horse power but the careful trade off could easily triple or quadruple the engines expected life span

    If you've ever hit a speed bump in the road thats meant to slow traffic, at several different speeds, you know theres a very noticeable relationship between the speed somethings moving and time it takes for inertia and mass of a moving object to change, direction when force is applied thru the use of a ramp changing its path of movement, and the resulting increase in shock to the components as the rate of that change over a shorter time is applied.
    a speed bump is similar to a cams lobe acceleration ramp, in that it lifts the lifter/valve against spring resistance similar to your cars wheel hitting the speed bump.
    a cams lobe design can rather gradually or rather suddenly impart a change in direction to the lifter in its bore and effect the speed at which the valve lifts off its seat or returns to a closed position, but that ramp design has a huge effect on the stress the valve train is subjected to as the speed of engine rotation is increased.
    just like your car hitting the speed bump in the road, theres a big difference at 7 miles per hour vs 70 miles per hour, and a cam lobe that pops the valves open at idle speed of 700rpm,imparts far less stress than the same lobe spinning at 7000rpm.
    naturally every choice is a compromise, lower lifts and smoother low acceleration rates make for long life and lower stress but restrict the potential area open under the valve per degree of rotation, which restricts potential breathing of the engine.
    rapid ramp acceleration rates tend to increase potential hp but impart higher stress

    Isky claims that the Comp XE cams violate the 47.5% rule.
    The 47.5% rule applies to flat tappet cams for SBCs with 1.5 rockers but the concept is still the same for other configurations where the designs are "on the edge" or "over the edge" for lobe intensity.
    For 1.5 ratio SBCs, the duration at .50 must exceed 47.5% of the total valve lift or your asking valve train problems.
    For example, take a Comp Cams Magnum 280H, with 230 duration and, 480 lift...230/.480 = 47.9% which exceeds 47.5% therefore would not pose a threat to components.
    We do not regularly hear about the older, safer HE and Magnum designs rounding off lobes anywhere near as often as the XE cam designs.
    Unfortunately, some of the Comp Cams XE dual pattern lobes break this 47.5% rule on the intake side so they are likely to be problematic.
    The design has "steeper" ramps that are too quick for durability and reliability according to most other cam manufacturers.
    They will wipe lobes in a heart beat especially if you have not followed the proper break-in procedure.
    Other designs are more forgiving during break-in and less likely to fail.

    that IS VERY TRUE, I know from experience that there's ALWAYS been more people who want engines built than I, or any other shop that developed a reputation for doing quality work, could come close to handling,
    the issue I found long ago is that very few really want to take the time required or get personally involved, or pay for the time and attention to detail it requires.
    If you get someone personally involved with a hands on approach , where you explain every step, the options and costs and THEY pay for the machine work or DO the work themselves they get a FAR better understanding of why it takes time and money to do the job correctly, and if they see a $2300 labor bill they don,t instantly think
    but rather, DAMN that's reasonable' for all the time and supplies that required.
    I don,t think I,d want to do that for that little money!

    the basic fact is, that as an engine builder there's two extremes,
    AS an engine builder ,you need to find a compromise
    between knocking piece work out like cookies,
    where I see many shops operate,like this,
    where they basically take a gasket set,
    some engine components and sealants and start bolting together parts.
    this requires minimal time or knowledge and results in an engine build,
    where you really don,t give a a rats ass if it does much more than run without breaking down,

    and the shops taking the time and effort to maximize every facet and check every components fit finish and function,
    which if done correctly would result in labor time charges alone, in a cost that would quadruple an engine ,
    normal machine shop assembly's cost average.
    theres always going to be a big difference between
    close enough so it won,t cause problems and

    the problem, is that unless your checking account balance, won,t notice the cost, like
    Jay-lenno and have an on site machine shop and staff, you always are forced to cut expenses, not select the best possible parts,
    and you can,t ignore the time and labor costs, you make a compromise, someplace.


    related info

    you tend to have to watch a couple dozen guys assemble engines and, do it while you pay real attention, and/ or
    watch several dozen similar videos to get that perspective and pick up the little differences and omissions in how each guy approaches and completes the process.
    yes youll undoubtedly see some guys skip over or ignore things that other guys feel are critical, but if you pay attention and really think things through and stop and ask your self
    (why is that guy bothering to take the time to bevel that bearing edge)
    (why is that guy verifying the oil pump stud does NOT touch the rear main cap bearing shell)
    , or
    (what the hell is a thrust bearing?)
    (what was the oil pump drive shaft to distributor gear clearance?)
    (what were those rod and main bearing clearances?)
    (how did he verify the piston to bore clearance?)
    (how do you verify rod bolt clamp or stretch?)
    (how do you get the damn damper on)
    (what the hell is quench)
    (compression height?)
    (maximizing ring seal to bore)
    (what do you mean don,t beat on that damper?)

    engine assembly is mostly the hard logical application of physical science with a bit of intuition, where the engine assembly technician and engineering testing is used to verify exactly what is and what is not functioning as its intended too.
    the fact is that the engineers and computer simulations can get things about 80% -to-85% to being as close to ideal, but the fact is the guys that control production costs and emission controls will always have some input and the production engineers will make cost reducing changes in the designs, the individual engine builder will get their hands on the O.E.M., engines and find ways to TWEAK, the as delivered engines to produce even better results, then the aftermarket will take a long hard look and start figuring out ways that they could further boost power with less concern for cost and emissions and a bit more concern for power output, then the engine builders will take those parts and TWEAK those parts and the cycle will continue several times until the original engines design has markedly been improved.
    I helped on of the local guys write out detailed instructions, had him stamp his major parts
    [​IMG] ... 60669.html

    with his last name on the block oil pan rails, crank flange and crank counter weights, cylinder heads, etc. and had him take a dozen clear picture's, of the engine components he was dropping off at the local machine shop, I strongly suggested he have a detailed list of what was to be done, the cost and a firm date set as to the expected completion of the work and to get a signed copy for both the machine shop and him to keep on hand, I don,t think this will be an issue simply because its the same machine shop I generally use and the guys rather familiar with my process and dozens of previous engine builds, but I've found through long years of experience, that if you don,t get a firm price listed exactly detailing the work to be done, and delivery date and yes you,ll need too keep, a signed copy of detailed work to be done, the machine work tends to constantly either get put off as more urgent work from other customers is brought in, or the work is only partially completed and not finished or the prices tend to increase far higher than originally quoted.
    it seems that most machine shops don,t want to make firm price or delivery date commitments and they have in some cases a habit of loosing or miss placing parts that were not listed and one you don,t have a picture of.
    most machine shops seem to work on, a
    " stop back in a week or so, it should be done by then"
    and "that should cost about $xxx ..
    but we have to see whats required on time and materials used basis"

    if you don,t nail down a firm date and price
    and all the details it could and usually will take well over a month,
    and easily cost significantly more than you were quoted.
    now obviously as parts are inspected prices and work required could change,
    but you want the machine shop to keep you up to date on exactly,
    whats being done, and the cost and changes in expected delivery dates.
    BTW it seldom hurts to try to be friendly and ask for the machinists advice,
    and complement him if he does good quality work ,
    thats delivered at the agreed date and price,
    and let him know you appreciate the skills, and on time delivery

    yes you do tend to find that the good quality work costs more.
    but the real cost of cheap work is far higher in many cases,
    especially when something fails resulting in catastrophic damage.
    a good machinist will generally, point out the inspections, tests and checks,
    required to build an engine thats far less likely to have problems.
    keep in mind that if you fail to take that advice and skip adding mods like,
    the proper baffled oil pan, several machining and clearance checks,
    or buying the parts, that best match the intended rpm/power range, you run a larger risk of failure.
    I've regularly had guys I built engines for ignore suggested components and substitute cheaper parts.
    in a few cases this results in rather badly mis-matched parts.(or skipping suggested machine work)
    yes you may save several hundred dollars if you select to port stock heads rather than buy aftermarket heads
    or use a stock crank, vs a 200%-to-300% plus stronger aftermarket components.

    I've found BRODIX I.K. heads are very good quality, and decent value per dollar,
    for a high performance street/strip style engine

    trickflow 230cc makes a good racing sbc head choice

    profiler 210cc is a good compromise race and street strip head

    related info
    USE THE CALCULATORS to match port size to intended rpm levels... but keep in mind valve lift and port flow limitations[/color]

    a couple known dependable engine builders
    Last edited: Apr 7, 2018
    Loves302Chevy likes this.

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