thoughts on 302sbc vs 383 sbc dyno results

grumpyvette

Administrator
Staff member
I recently got a fairly detailed question from a different site from a guy who wanted to build and old school 302 sbc to put in his 1968 camaro with a long list of old school components , starting with a set of older stock fuelie heads and an original z28 single four barrel dual plane intake, a 10:1 compression short block and the old original flat tappet solid lifter cam. I thought it might be useful to run a few software dyno comparisons comparing old school parts vs newer parts to illustrate why most guys no longer bother building the high rpm 302 small block combos using the old 1960s technology fuelie heads.

In 1966, General Motors designed a special 302 cu in (referred to as 5.0 L) engine for the production Z/28 Camaro in order for it to meet the Sports Car Club of America (SCCA) Trans-Am Series road racing rules limiting engine displacement to 305 cu in from 1967 to 1969. It was the product of placing the 283 cu in 3.00 in. stroke crankshaft into a 4.00 bore 327 cylinder-block. The 1967 302 used the same nodular cast-iron crankshaft as the 283, with a forged-steel crank that was also produced. This block is one of three displacements, 302/327/350, that underwent a crankshaft bearing diameter transformation for 1968 when the rod-journal size was increased from the 2.00 in. diameter small-journal to a 2.10 large-journal and the main-journal size was increased from 2.30 in. to 2.45. The large-journal connecting rods were thicker (heavier) and used 3/8 in. diameter cap-bolts to replace the small-journal's 11/32. 1968 blocks were made in 2-bolt and 4-bolt versions with the 4-bolt center-three main caps each fastened by two additional bolts which were supported by the addition of heavier crankcase main-web bulkheads. When the journal size increased to the standard large-journal size, the crankshaft for the 302 was specially built of tufftride-hardened forged 1053-steel and fitted with a high-rpm 8.00 in. diameter harmonic balancer. It had a 3/4-length semi-circular windage tray, heat-treated, magnafluxed, shot-peened forged 1038-steel 'pink' connecting rods, floating-pin in `69, forged-aluminum pistons with higher scuff-resistance and better sealing single-moly rings. Its solid-lifter cam, known as the '30-30 Duntov' cam named after its .030/.030 in. hot intake/exhaust valve-lash and Zora Arkus-Duntov (the first Duntov cam was the .012/.018 1957 grind known as the '097, which referred to the last three digits of the casting number) the "Father of the Corvette", was also used in the 1964-65 carbureted 327/365 and F.I. 327/375 engines. It used the '202' 2.02/1.60 valve diameter high-performance 327 double-hump `461 heads, pushrod guide plates, hardened 'blue-stripe' pushrods, edge-orifice lifters to keep more valvetrain oil in the crankcase for high-rpm lubrication, and stiffer valvesprings. In 1967, a new design high-rise cast-aluminum dual-plane intake manifold with larger smoother turn runners was introduced for the Z/28 that the LT-1 350 1969 Corvette and 1970 Z/28 engines were equipped with until the Q-jet carburetor returned in 1973. Unlike the Corvette, the exhaust manifolds were the more restrictive rear outlet 'log' design to clear the Camaro chassis's front cross-member. It had a chrome oil filler tube in the front of the intake manifold next to the thermostat housing from 1967 to 1968, and the first year unique chrome valve covers that had Chevrolet stamped into them without an engine displacement decal pad. In 1968 the engine had the chrome covers, but without the Chevrolet name, that had air cleaner breather and PCV valve grommets. In 1968, a chrome 14.00 x 3.00 in. drop-base open-element air cleaner assembly on a 780cfm vacuum secondary Holley 4-Bbl carburetor. A 'divorced' exhaust crossover port heated well-choke thermostat coil was used to provide cleaner and faster engine warm-up. Its single-point distributor had an ignition point cam designed to reduce point bounce at high rpm along with a vacuum diaphragm to advance ignition timing at idle and part-throttle for economy and emissions. Pulleys for the balancer, alternator, water-pump, as well as optional power-steering, were deep-groove to retain the drive belt(s) at high rpm. In 1969, the 302 shared the finned cast-aluminum valve covers with the LT-1 350 Corvette engine. Conservatively rated at 290 hp (216 kW) (SAE gross) at 5800 rpm and 290 lb-ft at 4800, actual output with its production 11:1 compression ratio was around 376 hp (280 kW) with 1.625 in. primary x 3.00 secondary tubular headers that came in the trunk when ordered with a 1967 Z/28, and associated carburetor main jet and ignition timing tuning[citation needed]. In 1968, the last year for factory headers, they had 1.750 in. primaries x 3.00 secondaries on our . A stock 1968 Z/28 with the close-ratio transmission, optional transistorized-ignition and 4.88 gear, fitted with little more than the factory plenum cowl cold-air hood induction and headers, was capable of running 12.9 second/108 mph 1/4-mile times on street tires.

note close ratio 4 speed 4.88:1 gears etc.

keep in mind theres no real replacement for added displacement
the increase from 350-383 in a sbc generally benefits you in two ways, it obviously adds the 33 extra cubic inches of displacement
and youll generally find your N/A engine makes about 1-1.3 hp and ft lb of torque per cubic inch, it also tends to effectively increase compression if the similar piston design is used simply because you compressing an increased volume per cylinder into the same size combustion chamber.
one other factor often over looked is the longer stroke of the 383 increase's mid and lower rpm port speeds this generally increases cylinder fill efficiency, in the lower and mid rpm ranges.
obviously if your going to supercharge or use turbos the piston and rods and crank assembly should be made to withstand the stress levels so a 4340 forged steel crank, forged pistons and after market forged connecting rods with the significantly stronger 7/16" ARP rod bolts are strongly suggested as is dropping the static compression to the 8:1 range to increase the potential volume of compressed fuel/air mix to be stuffed into and burnt above the piston.
Id point out that most transmissions are designed to shift at well under 6000 rpm and most hydraulic valve trains won,t retain best stability above about 6300 rpm, so going the 383 or the 406 SBC stroker route tends to maximize the SBC potential on a mild or mid range performance build
I did a quick DD2000 software dyno and heres what it predicted
302dy2.png


roughly 390hp/370 torque


because he wanted to use fairly cheap heads , I suggested swapping to extensively reworked vortec heads with mild porting and much better valve springs,
https://sdparts.com/index.php?q=details ... s/12558060
and a roller cam and a high rise single plane intake , the resulting software showed dyno this result, keep in mind its still a 302 with vortec heads that are extensively reworked, not stock.
now I also pointed out that there are 215cc versions of the vortec heads but i did not use or compare those heads
READ THE LINKS YOULL MISS A GREAT DEAL IF YOU SKIP THOSE
viewtopic.php?f=52&t=266&p=40004&hilit=215cc+vortec#p40004

http://www.superchevy.com/how-to/project-cars/sucp-1004-high-rpm-302-engine-build/

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

http://garage.grumpysperformance.com/index.php?threads/bare-minimum-tools.11026/#post-51823

http://garage.grumpysperformance.co...-calculators-and-basic-math.10705/#post-46737

http://garage.grumpysperformance.co...ing-tools-abrasives-sources.10683/#post-46207

http://garage.grumpysperformance.com/index.php?threads/cam-degreeing.9010/#post-35474

http://www.superchevy.com/how-to/project-cars/sucp-0903-302-small-block-engine-build/

http://www.camaros.org/forum/index.php?topic=7774.0

http://garage.grumpysperformance.com/index.php?threads/types-of-crankshaft-steel.204/

http://garage.grumpysperformance.co...i-just-picked-up-fuelie-heads-for-cheap.2099/

http://www.vintagemusclecarparts.com/pages/302crossram1.html

http://www.cnc-motorsports.com/short-blocks/small-block-chevy-4195/sb-chevy-302-short-blocks.html

If your intent on building a high rpm 302 think through the basics, its an engine that can only reach its potential with a SOLID LIFTER VALVE TRAIN that will allow it to operate in the 7000rpm plus range,and heads designed to flow at least 250 cfm at .500, and a cam with enough duration to allow the engine to breath effectively in the 6000rpm-7500rpm range easily, this will require matching the cam to a minimum of 10.5:1 compression,and a cam lift of over .500, it will REQUIRE a forged crank, a good quality forged rotating assembly components a dependable 6-7 quart baffled oil pan with a windage screen, that adds durability, all factory 302 z28 SBC cars used manual transmissions,and remember the power to weight ratio, a 302 may make good peak power in a fairly narrow rpm range but it will lack the potential torque of a larger displacement like a 377-406 SBC, so youll NEED to gear the car to operate within that effective power range, this traditionally requires 3.90:1-4.88:1 rear gears on a car used for 1/4 mile racing, and a 30-36 lb SFI billet steel flywheel and blow proof clutch for the inertia for a great launch and safety for 7500rpm gear shifts
read related links

http://garage.grumpysperformance.com/index.php?threads/a-brief-look-at-clutches.447/

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

http://garage.grumpysperformance.co...late-gear-ratios-and-when-to-shift-calcs.555/

http://garage.grumpysperformance.co...hing-the-drive-train-to-the-engine-combo.741/

http://garage.grumpysperformance.com/index.php?threads/types-of-crankshaft-steel.204/

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

http://garage.grumpysperformance.com/index.php?threads/connecting-rod-strength-h-vs-i-beam.1168/

http://garage.grumpysperformance.com/index.php?threads/whats-a-windage-tray-do.64/

302dy1.png

roughly 500hp/420 torque [/b]


notice the actual dyno test is not that far different
http://garage.grumpysperformance.com/index.php?threads/the-cross-ram-intake.623/#post-53061


keeping all those components above ,but swapping to a stroker crank to build a 383 displacement engine instead of a 302 ,with basically the same components being used as the second 302 showed this result
383dy1.png


now obviously I could get the combos to all produce better numbers and the vortec heads are a big restriction on the last 383, but I think its a useful bit of info showing the better parts boost the results noticeably and the roll a roller cam and increased displacement have in changing the basic power curve potential, and keep in mind the 383 has heads and a cam that are far from ideal, so its not showing its true potential

roughly 502hp/490 torque [/b]

this last software dyno shows the same 383 with the only additional change being the reworked vortec heads being swapped out for some 210cc afr aluminum heads to let the 383 breath

383dy2.png

roughly 550hp/500 torque ....roughly 130 horsepower and a 180ft lbs more torque, and most impressive is the jump in power in the 4000rpm-6000rpm power band over the original combo[/b]

302sbccr.png

heres something similar with a crane 114681 flat tappet solid lifter cam
crane114681.jpg

EDL-2925_OD.jpg


AFR 210 cc heads
210afrcom.png

edelbrock 2925 intake, holley 850 carb
roller rockers, long tube headers

http://garage.grumpysperformance.com/index.php?threads/heads-for-302-sbc.11492/#post-52993
 
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There is no doubt modern performance cylinder heads are better than most factory heads from the past Grumpy. Using modern Cams & Single plane intakes, cubic inch increase...power levels of 900 Hp to 1000 normally aspirated can be obtained easily.
If an individual can Fund the build $&$$,
Trend I have noticed is guys don't have a transmission or Rear Differential to handle the power levels at 500Hp & over.
They are Broke after building the engine.
Must feed the engine correct amount of Fuel at all times too.
List goes on.
 
High lift cams past .575" are hard on valvesprings on he street too.
Only best valvesprings will last for thousands of miles.
Goes back to your Philisophy of reliability .
The entire car built.
 
i dont think anyone can legitimately argue that given all the same parameters, more displacement = more torque. but you also have to consider alot of guys dont have the money to have a motor built... and even fewer guys have the knowledge to save some money and build one themselves.

of the guys that have the aptitude and the desire to build a motor themselves, only a few of them have a living situation that would allow it. you need some clean well lit space not everyone has a garage, and lots of specialty tools to assemble a motor... still a bit of an invesment. plus lotta guys may have all the above, but theyre married to a battle axe that wont allow it for whatever reason.

all else being equal i always agree that theres no replacement for displacement, but there are alot of factors that make a big motor unobtainable for alot of people. if power alone was a driving factor for every customer that asked me to work on his stuff... i would have to contract you to build motors full time grumpy! because theres no way me and my bud could do em all ourselves in any reasonable timeframe... unfortunately thats just not the case.

however... i dont see alot of push in any markets or any internet forums for guys to just start with a 400... why not? its even more displacement than a 383, and the 400 came in a bunch of cars you can pluck one at the boneyard for cheap. then keep your stock rotating assembly and do your heads, cam, intake and make more power for a smaller investment.

http://www.race-cars.net/calculators/compression_calculator.html

http://garage.grumpysperformance.com/index.php?threads/a-few-calculator-links.7108/#post-27382

http://www.projectpontiac.com/ppsite15/compression-ratio-calculator

http://www.wallaceracing.com/dynamic-cr.php

http://www.rbracing-rsr.com/comprAdvHD.htm

http://performancetrends.com/Compression_Ratio_Calculator_V2.3.htm

http://www.wallaceracing.com/cr_test2.php

http://www.pcengines.com.au/calculators/Calculate dynamic Comp Ratio.htm

http://www.csgnetwork.com/compcalc.html

http://www.diamondracing.net/tools/

https://www.uempistons.com/index.php?main_page=calculators&type=comp

https://www.rbracing-rsr.com/compstaticcalc.html
 
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your point about many guys not having the tools, skills or a place to work is reasonably valid yet Id point out that if the desire is truly there to build or own a big impressive engine the guys with that desire will eventually find a route to accomplish it.
one of my first engines was a rebuilt 389 Pontiac and the list of mistakes made could fill several pages yet it served a purpose, in that I did learn a great deal from making some really stupid mistakes, that I made, the next version was a 400 Pontiac, engine, that not only ran well, it made significantly better power that the original engine, this engine still had a long list of things done during its planing and assembly that I look back on and CRINGE , and shudder, just thinking about how it was far far from being correctly assembled.
but again I learned during the process and was forced to do a great deal of research and acquire a great many more tools, and make contacts with a more knowledgeable group of guys and machine shops.

Just learning from previous mistakes I made, asking detailed questions, and knowing what needed to be done and being able to recognize shoddy machine work, and knowing when the machine shop had either screwed it up or charged for work they never did or did very poorly was a huge step in gaining the skills and experience required in proper engine assembly.
I know several guys that have built very nice engines in open car ports and on engine stands they just covered with plastic trash bags and tarps while they waited for parts or machine work, (hardly ideal, and you always take a huge risk of parts being stolen that way) yet they did build and install engines they built that produced power exceeding the original engines power level and they all learned during the process.
heres a few traco sbc engines
3196.jpg

3197.jpg

3198.jpg

you might want to read thru these links

http://www.small-block-chevy.com/assemblyspec.html

http://www.brodix.com/uncategorized/ik-dyno

ID strongly suggest you keep firmly in mind that doing your math home work and selecting and correctly installing a few high quality well matched components , goes a long way towards building a durable high performance engine and its best to concentrate on maximizing the engines torque curve in the mid rpm range, up to the engines useful rpm red-line, and gearing the drive train to match that intended power band!
If your building a high performance street driven cars engine, ID try hard to build a combo that allows you to stay under about 4200 feet per minute in piston speed, maximizing the engines displacement, getting the dynamic compression close to 8:1 and carefully checking valve train clearances, and geometry.
building an engine with a Quench distance that falls in the .038-.044" range, and matching the cam duration, lift and LSA to the intended power band, and having headers that are designed to amplify cylinder scavenging in that power band, and carefully thinking through and installing a 7-8 quart baffled oil pan and windage screen along with use of high quality bearings, and valve train components, with carefully verified clearances ,goes a long way towards maintaining better long term durability!
YOU'LL tend to get what you pay for! in both parts quality and machine work precision, You'll almost never regret buying and carefully installing a few better quality forged rotating assembly parts or double or triple checking clearances, but you'll frequently wonder "W.T.F. WAS I THINKING"
if you buy cheap components or fail to verify clearances , if your bargain priced parts fail under stress!
do your reading and research home work before you buy parts!
if your not 110% sure of what you need stop and ask questions and get answers from several sources before proceeding on!


INFO THAT MIGHT BE USEFUL
http://www.chevy-camaro.com/faq/chevy-camaro-faq-Z28.shtm

related threads and useful info
you might be amazed at how much-related info,
is previously posted on this subject

http://garage.grumpysperformance.co...-stock-tpi-engine-components.1509/#post-74581

http://garage.grumpysperformance.co...rger-intake-runners-l98-tpi.13785/#post-72541

http://garage.grumpysperformance.com/index.php?threads/ideal-tpi-build.12203/#post-59273

http://garage.grumpysperformance.com/index.php?threads/bits-of-383-build-info.18/

http://garage.grumpysperformance.co...ps-on-building-a-tpi-383-c4.10434/#post-51507

http://garage.grumpysperformance.co...bes-hitting-connecting-rods.14687/#post-79310

http://garage.grumpysperformance.co...rebuild-old-dyno-results-new-cam-ideas.15332/

http://garage.grumpysperformance.com/index.php?threads/can-you-get-there-with-tpi.10494/

http://garage.grumpysperformance.com/index.php?threads/rods-to-close.2733/#post-7145

http://garage.grumpysperformance.com/index.php?threads/my-current-corvettes-383-combo.430/

http://www.superchevy.com/how-to/18459-chevrolet-corvette-c4-tpi-upgrades/

http://garage.grumpysperformance.co...ed-a-dual-58mm-throttle-body-on-your-tpi.290/

http://garage.grumpysperformance.co...-valve-spring-height-load-on-a-l98-383.14592/

http://garage.grumpysperformance.com/index.php?threads/small-base-circle-cams.3810/#post-72512

http://garage.grumpysperformance.com/index.php?threads/block-prep.125/

http://www.superchevy.com/how-to/engine ... hrods.html

http://www.hotrod.com/projectbuild/hrdp ... evy_build/
 
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http://www.superchevy.com/how-to/project-cars/sucp-1004-high-rpm-302-engine-build/

http://garage.grumpysperformance.com/index.php?threads/heads-for-302-sbc.11492/#post-52952

http://garage.grumpysperformance.com/index.php?threads/the-cross-ram-intake.623/#post-2154

http://garage.grumpysperformance.com/index.php?threads/heads-for-302-sbc.11492/#post-52993

http://www.hotrod.com/how-to/engine/302-small-block-chevy-engine-build/
theres zero doubt you can make really impressive power from a properly assembled 302 sbc engine, but Id point out that even back in the 1970s the hot ticket was to build a 377 , 383 or 406 displacement engine, simply because building an engine with the increased displacement HAS advantages, a 302 sbc needs to be able to spin up over 7500 rpm, in most effective combos this , will require a solid lifter flat tappet or roller valve train and a cam with enough duration to make its off idle performance below 3000 rpm less than ideal on a street driven car with gearing that will allow it to cruise effortlessly at 3000 rpm, its also going to require the use of a more expensive valve train.
yes a 302 SBC engine sounds damn impressive , and yes it can be quick, but it can be built even quicker if the correct components and a bit more displacements used in the build!
I think your missing the point here or perhaps don,t have a good grasp on two different but interacting physical issues, if you think you can, just stick the original z28 cam and lifters in a de-stroked 350 and go racing!
P12CHARTS.jpg

(1) piston speeds
you'll generally find about 4000 feet per minute as a safe MAXIMUM rpm with the BETTER stock CHEVY DZ-302 and 350 rotating assembly parts
4000 x 12/6=8000 rpm for a 302 with its 3" stroke
4000 x 12/7=6857 rpm for a 350 with its 3.5" stroke.
roughly a 1150 rpm higher safe rpm with the shorter stroke 302.
at roughly 6850 rpm the 350 has 57 power strokes PER SECOND
a 302 will have 67 PER SECOND at 8000 rpm
in either case a hydraulic lifter valve train will not maintain valve control at anywhere near those rpm levels and even the factory solid lifter valve springs and cam are not designed to operate effectively while maintaining valve train control at those rpm levels with the original z28 cam, if your serious youll want a more modern solid lifter cam, and surely better valve springs and a rocker stud girdle


if a 302 makes 1.2 horsepower per cubic inch your looking at 360 plus hp
if a 383 makes 1.2 horsepower per cubic inch your looking at 460 plus hp
a reasonable max limit on piston speed should be calculated and used in either build.
and at the same time the 383 is going to have 70-100 ft lbs more torque at 3000 rpm
and be able to produce that power with less valve train stress.
I'd also point out that the 302 was generally almost exclusively built to use a manual transmission, and clutch/flywheel explosions were hardly rare, when you power shift a 302 at 7500 rpm, if you've ever seen a flywheel nearly cut a car in half you'll remember why blow proof bell housings are strongly recommended.
As would be quality forged parts in the rotating assembly and a 4 bolt main stud block, IDEALLY with splayed main cap bolts.
E-11.jpg


17965ad7.jpg



btw I used to own a 1969 camaro, as did one of my best friends, his was a real Z28 and he eventually installed the dual quad cross ram intake,lakewood traction bars , that looked very similar to this offy picture posted here below, he thought the car was super fast, it had 4.11:1 rear gears and a 4 speed muncie trans, and regularly ran very high 12 second 1/4 mile times at the track
back in the early 1970s a street car that would run a true mid 12 second 1/4 mile time was rare despite what every old geezer who owned a 289 mustang or 390 fairlane will tell you.
READ THRU THIS THREAD

http://garage.grumpysperformance.com/index.php?threads/how-fast-were-the-old-muscle-cars.1938/
ACTUAL MAGAZINE ROAD TEST AT THE TIME
1969 Camaro SS396 (CL)
396ci/375hp, 4spd, 3.73, 0-60 - 6.8, 1/4 mile - 14.77 @ 98.72mph
1969 Camaro SS396 (PHR)
396ci/375hp, 3spd auto, 3.73, 0-60 - n/a, 1/4 mile - 14.48 @ 100.55mph
1969 Camaro Z/28 (PHR)
302ci/290hp, 4spd, 3.73, 0-60 - n/a, 1/4 mile - 14.74 @ 95.88mph
1969 Camaro Z/28 (CL)
302ci/290hp, 4spd, 4.10, 0-60 - 7.4, 1/4 mile - 15.12 @ 94.8mph

BTW HALF THE OLD GUYS I TALK TO SWEAR THEY USED TO OWN A NEARLY STOCK
11 second hemi road runner
1969 Plymouth Road Runner (CD)
426ci/425hp, 3spd auto, 3.54, 0-60 - 5.1, 1/4 mile - 13.54 @ 105.14
1969 Plymouth Road Runner (Speed & Supercar)
426ci/425hp, 3spd auto, 4.10, 0-60 - n/a, 1/4 mile - 13.32 @ 107.65mph

going FAST is mostly about GETTING YOUR TRANSMISSION GEARING TO MATCH THE ENGINES POWER CURVE,
your suspension,
AND TIRES TO PROVIDE MAXIMUM traction and HAVING
A HIGH power to weight ratio

GET THE CAR LIGHT WEIGHT ENOUGH AND YOU CAN DO AMAZING THINGS WITH MODERATE POWER LEVELS.
IF IT WEIGH'S A GREAT DEAL ,IT WILL BE MUCH HARDER ON PARTS ,REQUIRE LARGER BRAKES AND MUCH MORE POWER,TO GET THE CAR TO RUN QUICKER AND FASTER
READ THE LINKS USE THE CALCULATORS, AND think things through carefully

http://garage.grumpysperformance.co...-info-worth-reading-through.11528/#post-53210

http://garage.grumpysperformance.co...trans-choice-made-correctly.11697/#post-54833

manifoldcarbsrt0.jpg


2nd Design Off-Road cam, P/N 3965754
Casting #3965751
Intake 248 duration (324 advertised)
Exh. 267 duration (334 advertised)
Lift: .512" intake, .535" exhaust
the car looked and sounded real impressive!
(it could easily be a clone of the picture below)
camaro-z28-1969.jpg

camaro-z28-1969.jpg

my car was all white , but had the similar body style, to the Z28 cars
It originally came with the 375hp 396 engine and even in that config it was a bit faster than the Z28 my friend had .
and yeah I soon installed a 496 BBC stroker

below is a picture of me and that car back around 1972

paulscamarobw.jpg

and before anyone asks why the stupid hood scoop, it covered the CROWER INJECTION STACKS to reduce the chances of morons dropping crap down the stacks
Crower_Injectors.jpg

yeah I know many guys will ignore the links, its also likely to cost them in time and cash

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


http://garage.grumpysperformance.co...onnecting-rod-rod-length-too-stroke-info.510/

http://garage.grumpysperformance.com/index.php?threads/rods-that-don-t-destroy-your-budget.10958/

http://garage.grumpysperformance.co...ant-to-spin-a-sbc-to-8000rpm.8442/#post-29559

http://garage.grumpysperformance.com/index.php?threads/rod-bolts-rpm-vs-stress.341/

http://garage.grumpysperformance.co...-for-truck-build-sbc-engine.12050/#post-57645

http://garage.grumpysperformance.co...ng-rods-from-pressed-to-full-float-pins.6909/

http://garage.grumpysperformance.com/index.php?threads/redline.343/

http://garage.grumpysperformance.co...on-velocity-acceleration-wgt.6636/#post-21049

http://garage.grumpysperformance.co...good-street-combo-your-after.5078/#post-14840

http://garage.grumpysperformance.co...rive-train-to-the-engine-combo.741/#post-1048

http://garage.grumpysperformance.co...-ratios-and-when-to-shift-calcs.555/#post-841

http://garage.grumpysperformance.com/index.php?threads/port-speeds-and-area.333/#post-37693

http://garage.grumpysperformance.com/index.php?threads/heads-for-302-sbc.11492/#post-52952

http://garage.grumpysperformance.com/index.php?threads/z28-1st-2nd-design-cams.4463/

http://garage.grumpysperformance.com/index.php?threads/the-cross-ram-intake.623/

http://garage.grumpysperformance.co...eption-has-changed-over-time.8379/#post-29224
while a well built small block may get your car to run faster than the average street performance car a well built, high compression BIG BLOCK ENGINE (especially 500 cubes and up) and its huge increase in brute torque has a feeling thats totally different
VIN130.jpg
 
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because knowing ALL your options and your goals is mandatory to getting good results, I'd point out that the 1969 camaro came with the optional 375HP 396 BBC engine and I had a 496 stroker installed in my car for about a year before I sold the car and bought a 1968 corvette that I swapped that engine into!
you really should get these books and read them before going any further, it will help a good deal, yeah I KNOW, STARTING BUY BUYING A FEW PARTS IS MORE FUN!, BUT KNOWING EXACTLY WHICH PARTS AND WHY YOU SELLECTED THEM IS SMARTER
http://www.amazon.com/exec/obidos/ASIN/1...1234339-0571324
1557882169.01._PE30_PIdp-schmooS,TopRight,7,-26_SCMZZZZZZZ_.jpg

http://www.amazon.com/exec/obidos/tg/det...nce&s=books
0912656042.01._PE30_PIdp-schmooS,TopRight,7,-26_SCMZZZZZZZ_.jpg

http://www.amazon.com/exec/obidos/tg/det...nce&s=books
0895861755.01._PE30_PIdp-schmooS,TopRight,7,-26_SCMZZZZZZZ_.jpg

http://www.amazon.com/exec/obidos/tg/det...nce&s=books
1884089208.01._PE30_PIdp-schmoo2,TopRight,7,-26_SCMZZZZZZZ_.jpg

http://www.amazon.com/exec/obidos/tg/det...nce&s=books
1557883572.01._PE30_PIdp-schmoo2,TopRight,7,-26_SCMZZZZZZZ_.jpg

http://www.amazon.com/exec/obidos/tg/det...nce&s=books
0760302030.01._PE_PIdp-schmoo2,TopRight,7,-26_SCMZZZZZZZ_.jpg


http://garage.grumpysperformance.co...k-for-in-a-good-engine-combo.9930/#post-46399

http://garage.grumpysperformance.com/index.php?threads/another-496bbc.5123/

http://garage.grumpysperformance.com/index.php?threads/540bbc-335cc-afr-head-combo.10627/

http://garage.grumpysperformance.com/index.php?threads/big-block-head-comparison.319/

http://www.hotrod.com/how-to/engine/hrdp-0805-540-big-block-chevy-engine/

http://garage.grumpysperformance.com/index.php?threads/block-choice.10472/#post-43987
 
Last edited:
if your thinking of building any SBC that will exceed 6000rpm,
use nitrous or exceed about 550 hp I'D strongly suggest a SCAT forged rotating assembly, with 4340 steel, and 7/16: ARP rod bolts,
and a DART block be used, yeah! I know your thinking the costs just jumped up a great deal!
but if the OEM block flexes (which it will) at those stress levels and something like a main cap cracks,
or a rod bolt lets loose on that reconditioned OEM block with its much wealer and thinner casting, youll be lucky to save the intake and valve covers


if your willing to use an old school flat tappet solid lifter cam,
Id suggest a crane 110921 flat tappet solid lifter design,
obviously you can't reasonably select the right cam for any application,
without matching its intended valve timing to the application,
and other components to be used.

http://garage.grumpysperformance.com/index.php?threads/semi-fool-proof-cam-sellection.82/

a cam like this will come very close to maximizing the port flow on a fuelie head,
on a properly designed combo in a 327-400 sbc,
but its not ideal for a daily driver style cars engine application,
as its designed to operate in the 3500 rpm-about-6800 rpm power band,
in a engine with properly matched drive train ,
and other engine components,
clearances and valve train.
http://www.cranecams.com/product/cart.php?m=product_detail&p=23968
https://www.summitracing.com/parts/crn-110921

crane110921.jpg

that was a very well respected cam , used in the 1970s-90s
it made very respectable power,
its best with 10.5:1-11:1 compression and a dual plane intake like an edelbrock air gap,
and headers with a low restriction exhaust,
get the static compression down at 10:1 and degree the cam in strait up, you should get by with that 98 octane fuel.
and you'll want a manual trans or a 3200 stall converter and a 3.73:1 -4.11:1 gear,
most guys used a holley 750-780 cfm carb.
with 1.6:1 roller rockers and decent long tube open headers
,it' valve timing about maximized the power OEM, Chevy fuelie heads had available in most sbc engines

before you ask.
yes theres a similar version in a hydraulic flat tappet version, you get easy valve adjustment but it costs you a couple hundred rpm in peak power, and neither versions going to be ideal on anything but a serious performance car with the correct matched valve train, intake,headers,gearing etc., remember this class of cams is designed for road racing and drag, racing and serious performance with matched tires, suspension , gearing etc where youll rarely have the engine spinning under 3500 rpm
crane110741.png


http://www.enginelabs.com/engine-tech/engine-blocks/debate-dart-shp-or-restored-stock-block/


http://garage.grumpysperformance.com/index.php?threads/block-choice.10472/

http://garage.grumpysperformance.com/index.php?threads/re-little-m-sportman-shp.2229/

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

http://garage.grumpysperformance.com/index.php?threads/engine-block-cylinder-wall-thickness.976/

http://garage.grumpysperformance.com/index.php?threads/sbc-cylinder-wall-thickness.7646/

http://garage.grumpysperformance.com/index.php?threads/valve-train-shrapnel-screens.1458/

http://www.scatcrankshafts.com/downloads/14scat_catalog_10-13.pdf

http://garage.grumpysperformance.com/index.php?threads/types-of-crankshaft-steel.204/#post-44395

http://www.dartheads.com/products/engine-blocks

OEM BLOCKS , are NOT as strong as the THICKER AFTERMARKET BLOCKS
main%20web%20crack.jpg

bblock.jpg

chevblockparts003.jpg


why cast cranks and high stress and rpm are a bad idea

00781.jpg

00773.jpg

brokencrank.jpg

 
Last edited:
while I'm fairly sure most of the guys reading through the thread will ignore the links, its going to cost them to ignore the info
while I'm sure the first reaction will be to skip reading through hours of linked info the fact is that having that resource available will save you weeks of wasted effort and thousands in wasted cash
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.

Read it, print it out, and tape it to your beer fridge. (Quick—while your sixth grade teacher isn’t looking!)

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
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
Horsepower = (RPM x Torque) ÷ 5,252

Torque
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

http://garage.grumpysperformance.com/index.php?threads/down-the-rabbit-hole-with-alice.10933/


http://garage.grumpysperformance.com/index.php?threads/tbucket-engine-project-dart-shp.3814/

http://garage.grumpysperformance.com/index.php?threads/what-to-look-for-in-a-good-engine-combo.9930/

http://garage.grumpysperformance.com/index.php?threads/matching-parts-and-a-logical-plan.7722/

http://garage.grumpysperformance.co...uild-the-engine-to-match-the-cam-specs.11764/

http://garage.grumpysperformance.co...1-6-1-ratio-rockers-and-the-pushrods-rub.198/

http://garage.grumpysperformance.co...lding-a-350-or-upgrading-too-a-383-sbc.11408/

http://garage.grumpysperformance.com/index.php?threads/heads-for-302-sbc.11492/

http://garage.grumpysperformance.co...ghts-on-302sbc-vs-383-sbc-dyno-results.10210/

http://garage.grumpysperformance.co...-the-charts-calculators-and-basic-math.10705/

http://garage.grumpysperformance.com/index.php?threads/finding-a-machine-shop.321/

http://garage.grumpysperformance.co...ty-thats-key-in-building-a-good-engine.11682/

http://garage.grumpysperformance.com/index.php?threads/the-cross-ram-intake.623/

http://garage.grumpysperformance.co...i-just-picked-up-fuelie-heads-for-cheap.2099/

http://garage.grumpysperformance.com/index.php?threads/the-cross-ram-intake.623/#post-2154
 
Last edited:
327for.jpg

heres a fairly common basic guide on how to build a serious 327-331 SBC race only combo,
any engine like this in a fairly light weight car (keep it in the 2300 lb-2600 lb MAX WEIGHT range if you can)
with about a 28"-29" tall set of slicks , a properly set up differential and suspension and probably 4.11-4.56:1 rear gears (personally THIS SCREAMS , a MANDATORY DANA 60 or ford 9" and billet axles, too me)
and ID strongly suggest, a 4500-5000 rpm stall converter ,
should do reasonably well in local bracket racing, but this type of engine combo,
is not going to be at all useful as transportation, and it will need to be pulled down and carefully inspected after every season,
or after no more than maybe 40-60 1/4 mile runs.
yes you could build a rather similar combo in a 383-406 and expect even more power and torque, but less power per cubic inch of displacement,
and of course the basic power and rpm range would be in a lower average rpm band as the longer stroke requires the lower max rpms to keep piston speeds reasonable.
ID also strongly suggest the obvious mandatory used of a much stronger after market block and ALL forged 4340 crank and rods and forged pistons
yes you could get even more power if you used larger heads and boosted the compression up into the 13.7:1 range with the larger displacement but your just as obviously forced to use either something like 112 octane race gas or an 70% ethanol/race octane gas alcohol fuel. and if your going that route stack injection is probably as better route than a dual quad tunnel-ram induction intake to feed it, Id certainly be looking at aluminum heads that flow well in excess of 300 cfm at .600 lift and a set of open headers with carefully calculated dimensions to maximize cylinder scavenging.
remember the basics

(1)the better it breaths with the less flow restriction, the more potential power youll have available
(2) exhaust scavenging must match cam timing and displacement and compression
(3) if the rotating assembly and valve train won,t hold up too the intended stress and rpms it won,t last long
(4)the drive train and gearing must match the power/rpm band)
(5) if its not well lubricated and adequately cooled it WILL come apart in a violent and expensive manor , its just a mater of time!
(6) buying crap quality heads to save cash then trying to get more power is a bit like beating a dead horse to get it too run faster... the amount of time and effort spent doing that will still not improve the results.
(7) a few well matched, high quality parts is generally going to produce far better results that an equally expenditure of far more low quality components

if two otherwise identical cars, that are properly geared, and the properly set up suspension,
that weight the same,are matched, the one with a 302 sbc vs a properly built 377, -383-406 SBC
will be at a DIS-advantage!
theres zero question a 302 sbc can produce impressive power per cubic inch of displacement,
but you can,t dispute physics
more displacement tends to result in more torque and as a result potentially more power.
if a 302 makes 1.5 hp per cubic inch, thats roughly 450 hp
if a 383 only makes 1.3 hp cubic inch, thats roughly 500 hp
Id also point out that with current after market components,
the 383-406 can make exceptional power.
and the 383 will generally have 60-80 ft lbs more torque over most of the rpm range
put both engines in a 1969 camaro and the larger displacement engine tends to show the 302 tail lights...
been there done that , proven that dozens of times.


Im certainly not the only one that noticed the results
currently theres hundreds of kits to build 383-406 SBC,
very few places still sell 302-327 kits because most experienced engine builders acknowledge,
the power per dollar spent advantage of the larger displacement SBC
ESPECIALLY if limited to pump octane gas being used
I.m certainly not suggesting that a kick ass and take names 302 can,t be built,
Ive built several in the past,
but I'm forced to point out my experience over decades that its not always the best use of the money,
and time spent if the goal, is to build the most hp per dollar spent.
keep in mind the main advantage that the 302 SBC potentially has is due to the short 3" stroke
piston speed in most SBC should rarely exceed, some rather well proven physical limitations.
to take full advantage of that high rpm potential youll want to use a solid flat tappet or ideally a solid roller lifter valve train assembly with a rocker stud girdle, and all forged rotating assembly components
youll need a 6-8 quart baffled oil pan, seriously larger port heads than the original 165cc port fuelie heads, and a well designed set of headers and exhaust system.
simply because youll be running up in the 7500-rpm-8000 rpm power band and no mater what the cam manufacturer advertising states thats NOT hydraulic lifter territory.
If the goal is max power from a 302, displacement, Ideally youll want to use 11:1-to-12.7"1 compression and that mandates either race gas or alcohol fuel.

http://garage.grumpysperformance.com/index.php?threads/redline.343/#post-15729

http://garage.grumpysperformance.co...od-rod-length-too-stroke-info.510/#post-12292

http://garage.grumpysperformance.com/index.php?threads/calculating-ideal-port-size.624/#post-8692

http://garage.grumpysperformance.com/index.php?threads/types-of-crankshaft-steel.204/

http://garage.grumpysperformance.com/index.php?threads/rod-bolts-rpm-vs-stress.341/#post-30778

http://garage.grumpysperformance.com/index.php?threads/connecting-rod-strength-h-vs-i-beam.1168/





ID suggest you select from heads from these sources

Jegs; 800/345-4545; Jegs.com

Summit Racing; 800/230-3030; SummitRacing.com

Scoggin-Dickey Parts Center; 800/456-0211; ScogginDickey.com


TRICKFLOW
http://www.trickflow.com/egnsearch.asp? ... 4294867081
http://www.trickflow.com/customerservice
1-330-630-1555 • 1-888-841-6556

BRODIX
http://www.brodix.com/heads/heads.html
479.394.1075

DART
http://www.dartheads.com/products/cylinder-heads
Dart Machinery; 248/362-1188; DartHeads.com


AIR FLOW RESEARCH
http://www.airflowresearch.com/
toll free: 877-892-8844
tel: 661-257-8124

Patriot Performance
Patriot Performance; 888/462-8276; Patriot-Performance.com


RHS
http://www.racingheadservice.com/rhs/cylinder-headshtml
Toll Free: 877-776-4323
Local: 901-259-1134

EDELBROCK
http://www.edelbrock.com/automotive_new ... main.shtml
Edelbrock; 310/781-2222; Edelbrock.com

BMP (world products)
http://www.theengineshop.com/products/cylinder-heads
Tel: 631-737-0372
Fax: 631-737-0467

BUTLER PERFORMANCE
http://www.butlerperformance.com/products/cylinder_heads/cylinder_head_labor.html
866-762-7527

BLUE PRINT ENGINES
http://www.blueprintengines.com/ind...sb-chevy-aluminum-cylinder-heads-cnc-machined
1800-483-4263

PRO-FILER
https://www.profilerperformance.com/
937‐846‐1333



“Quality means doing it right when no one is looking.”
Henry Ford

“Quality is like buying oats. If you want nice, clean, fresh oats, you must pay a fair price. However, if you can be satisfied with oats that have already been through the horse ... that comes a little cheaper.”

an hour to a week spent in careful research,
before you buy or install parts,
can save you months or frustration
and easily 300%-to 500% of the eventually,
cost incurred in buying cheaper parts,in this hobby!


http://garage.grumpysperformance.com/index.php?threads/sellecting-cylinder-heads.796/

https://www.enginelabs.com/news/dyno-video-mike-saikis-23-degree-small-block-makes-806-horses/

https://www.jegs.com/i/AFR/033/1068...MIsdGis5j33AIVSb7ACh23EARDEAQYBSABEgImSfD_BwE
 
Last edited:
327for.jpg

heres a fairly common basic guide on how to build a serious 327-331 SBC race only combo,
any engine like this in a fairly light weight car (keep it in the 2300 lb-2600 lb MAX WEIGHT range if you can)
with about a 28"-29" tall set of slicks , a properly set up differential and suspension and probably 4.11-4.56:1 rear gears (personally THIS SCREAMS , a MANDATORY DANA 60 or ford 9" and billet axles, too me)
and ID strongly suggest, a 4500-5000 rpm stall converter ,
should do reasonably well in local bracket racing, but this type of engine combo,
is not going to be at all useful as transportation, and it will need to be pulled down and carefully inspected after every season,
or after no more than maybe 40-60 1/4 mile runs.
yes you could build a rather similar combo in a 383-406 and expect even more power and torque, but less power per cubic inch of displacement,
and of course the basic power and rpm range would be in a lower average rpm band as the longer stroke requires the lower max rpms to keep piston speeds reasonable.
ID also strongly suggest the obvious mandatory used of a much stronger after market block and ALL forged 4340 crank and rods and forged pistons
yes you could get even more power if you used larger heads and boosted the compression up into the 13.7:1 range with the larger displacement but your just as obviously forced to use either something like 112 octane race gas or an 70% ethanol/race octane gas alcohol fuel. and if your going that route stack injection is probably as better route than a dual quad tunnel-ram induction intake to feed it, Id certainly be looking at aluminum heads that flow well in excess of 300 cfm at .600 lift and a set of open headers with carefully calculated dimensions to maximize cylinder scavenging.
remember the basics

(1)the better it breaths with the less flow restriction, the more potential power youll have available
(2) exhaust scavenging must match cam timing and displacement and compression
(3) if the rotating assembly and valve train won,t hold up too the intended stress and rpms it won,t last long
(4)the drive train and gearing must match the power/rpm band)
(5) if its not well lubricated and adequately cooled it WILL come apart in a violent and expensive manor , its just a mater of time!
(6) buying crap quality heads to save cash then trying to get more power is a bit like beating a dead horse to get it too run faster... the amount of time and effort spent doing that will still not improve the results.
(7) a few well matched, high quality parts is generally going to produce far better results that an equally expenditure of far more low quality components


ID suggest you select from heads from these sources
Jegs; 800/345-4545; Jegs.com

Summit Racing; 800/230-3030; SummitRacing.com

Scoggin-Dickey Parts Center; 800/456-0211; ScogginDickey.com


TRICKFLOW
http://www.trickflow.com/egnsearch.asp? ... 4294867081
http://www.trickflow.com/customerservice
1-330-630-1555 • 1-888-841-6556

BRODIX
http://www.brodix.com/heads/heads.html
479.394.1075

DART
http://www.dartheads.com/products/cylinder-heads
Dart Machinery; 248/362-1188; DartHeads.com


AIR FLOW RESEARCH
http://www.airflowresearch.com/
toll free: 877-892-8844
tel: 661-257-8124

Patriot Performance
Patriot Performance; 888/462-8276; Patriot-Performance.com


RHS
http://www.racingheadservice.com/rhs/cylinder-headshtml
Toll Free: 877-776-4323
Local: 901-259-1134

EDELBROCK
http://www.edelbrock.com/automotive_new ... main.shtml
Edelbrock; 310/781-2222; Edelbrock.com

BMP (world products)
http://www.theengineshop.com/products/cylinder-heads
Tel: 631-737-0372
Fax: 631-737-0467

BUTLER PERFORMANCE
http://www.butlerperformance.com/products/cylinder_heads/cylinder_head_labor.html
866-762-7527

BLUE PRINT ENGINES
http://www.blueprintengines.com/ind...sb-chevy-aluminum-cylinder-heads-cnc-machined
1800-483-4263

PRO-FILER
https://www.profilerperformance.com/
937‐846‐1333



“Quality means doing it right when no one is looking.”
Henry Ford

“Quality is like buying oats. If you want nice, clean, fresh oats, you must pay a fair price. However, if you can be satisfied with oats that have already been through the horse ... that comes a little cheaper.”

an hour to a week spent in careful research,
before you buy or install parts,
can save you months or frustration
and easily 300%-to 500% of the eventually,
cost incurred in buying cheaper parts,in this hobby!


http://garage.grumpysperformance.com/index.php?threads/sellecting-cylinder-heads.796/

https://www.enginelabs.com/news/dyno-video-mike-saikis-23-degree-small-block-makes-806-horses/

https://www.jegs.com/i/AFR/033/1068...MIsdGis5j33AIVSb7ACh23EARDEAQYBSABEgImSfD_BwE

That Engine Combo only makes sense if you own a 1963 Chevy II Duece .
And for Nostalgia Super Stock Racing.
It would be fast.

Not enough torque to compete with the Pontiac V8 455 - 400 RAIV.

Big Chevy would spank it too Grumpy.
 
Last edited by a moderator:
Guys are cheep Grumpy.
Hate buying Titanium needed for high Rpms.
6500-6600 rpm all power in a good target for drag strip.
 
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