302 chevy
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,443
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
I've built a few 396 ci small blocks that all turn 7500 rpm. 4.030 X 3.875 stroke
It is very easy to do. Forged rotating assembly, heads that flow over 300 cfm intake, Solid roller cam in the high 240's duration, single plane with 750+ cfm
A highly tuned motor can make @ 1.32 foot pounds of TQ per cubic inch.
1.25 is actually closer to street machines with high compression with big heads.
But 302 x 1.32 = 398.64
396 x 1.32 = 522.72
122 additional foot pounds will rev. faster in gear by a massive amount. At the drag strip a 302 might break 14.00 seconds and the 396 is good for 11.50
Then just put your 302 emblems on it.
It is very easy to do. Forged rotating assembly, heads that flow over 300 cfm intake, Solid roller cam in the high 240's duration, single plane with 750+ cfm
A highly tuned motor can make @ 1.32 foot pounds of TQ per cubic inch.
1.25 is actually closer to street machines with high compression with big heads.
But 302 x 1.32 = 398.64
396 x 1.32 = 522.72
122 additional foot pounds will rev. faster in gear by a massive amount. At the drag strip a 302 might break 14.00 seconds and the 396 is good for 11.50
Then just put your 302 emblems on it.
Last edited by gkull; Aug 9, 2011 at 11:44 AM.
Le Mans Master
Joined: Jun 2004
Posts: 6,231
Likes: 65
From: Seattle WA
St. Jude Donor '14
Agreed, to some extent. They're certainly not a Holy Grail by any means, but the high nickel/high tin blocks do have better wear (not strength) qualities. Anymore it's pretty darn tough to find these that haven't been overhauled multiple times.
Any GEN I block in decent condition will hold to around 1.2 HP/CID or better...although if you're going to spin it consistently past about 5.8K I would certainly have the block align-honed and pay very close attention to balance. But with the relatively low cost of aftermarket blocks, the uncertainty of GEN I used blocks anymore and expen$ive machine work, it's worth looking at an aftermarket block.
This is all before we start talking about high RPM valvetrain dynamics
Screamer SBCs ain't cheap 
Any GEN I block in decent condition will hold to around 1.2 HP/CID or better...although if you're going to spin it consistently past about 5.8K I would certainly have the block align-honed and pay very close attention to balance. But with the relatively low cost of aftermarket blocks, the uncertainty of GEN I used blocks anymore and expen$ive machine work, it's worth looking at an aftermarket block.
This is all before we start talking about high RPM valvetrain dynamics
Screamer SBCs ain't cheap
Le Mans Master
Joined: Sep 2001
Posts: 7,739
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From: Unreconstructed, South Carolina
327 ... never actually known one like it, but ...
+40 over 400 block
3" stroke
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now have a 377 sitting around ... +30 over 400 block, manley platinum popups, 6" manley I-beams, steel 350 GM crank ... combo was the cat's meow in circle track ... may remain so ... somewhere.
----------------------------------------
At one time, many nascar motors were based on a 400 block w/ 327 crank.
+40 over 400 block
3" stroke
----------------------------------------
now have a 377 sitting around ... +30 over 400 block, manley platinum popups, 6" manley I-beams, steel 350 GM crank ... combo was the cat's meow in circle track ... may remain so ... somewhere.
----------------------------------------
At one time, many nascar motors were based on a 400 block w/ 327 crank.
Le Mans Master
Joined: Jun 2004
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From: Seattle WA
St. Jude Donor '14
Didn't Smokey Yunik do some sort of massively oversquare engine thing for his Indy car? I'll have to dig out my old Secrets book and look tonight, but thought I'd see if anyone remembered...
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,443
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
http://www.ghostmodels.com/?car;item=606;view=14
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Le Mans Master
Joined: Oct 2010
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From: melbourne florida
2023 C3 of the Year Finalist - Modified
i remember that engine. my theory on why he did that was to utilize the tendancy for hot gas to rise and also to keep the intake charge cooler. i remember the bundle of snakes headers being where the intake would normally be. I'd hate to try to package that in a street car.
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,443
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
i remember that engine. my theory on why he did that was to utilize the tendancy for hot gas to rise and also to keep the intake charge cooler. i remember the bundle of snakes headers being where the intake would normally be. I'd hate to try to package that in a street car.
The idea is ease of the best header sign. Heat keeps velocity up. Ferrari's V-12's have 3 into 1 and 4 megaphone collectors Very highly tuned 10,000 + rpm engines from the 60's The V-8 pipes were adjacent firing cylinders 4 into 1 known as 180 degree headers with two megaphones
I work on these motors!
Thread Starter
Le Mans Master
Joined: Apr 2006
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If i did a 302 it would not be a realistic street car. You put big time compression, camming, gears in a motor that small or your wasting your time.
Where i live to much population to do street car. Have to drive it 40 miles to get where you might get away with something.
Where i live to much population to do street car. Have to drive it 40 miles to get where you might get away with something.
Le Mans Master
Joined: Jun 2004
Posts: 6,231
Likes: 65
From: Seattle WA
St. Jude Donor '14
One of our clients bought this car and it was in our shop for work. It has Smokey Yunik as the engine builder. Very radical double over head cam. Injector stacks on the outside and the 8 exhaust pipes on top where the carb and intake usually sit. It is a Ford motor.
http://www.ghostmodels.com/?car;item=606;view=14
http://www.ghostmodels.com/?car;item=606;view=14
Le Mans Master
Joined: Jun 2004
Posts: 6,231
Likes: 65
From: Seattle WA
St. Jude Donor '14
I'm not the OP...but I have built a few 377's here and there.
I have to admit to being a 350/383 guy pretty much exclusively in GEN I SBCs. I have built a few 396's...but found them to be more work and expense than the 13 CID was worth...just one guy's opinion.
I have to admit to being a 350/383 guy pretty much exclusively in GEN I SBCs. I have built a few 396's...but found them to be more work and expense than the 13 CID was worth...just one guy's opinion.
Instructor
Joined: Mar 2010
Posts: 228
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From: Evansville WI
'92-'97 LT1 block, '94-'96 L99 crank = the magical 302 using commonly available(re: cheap and easy to get) factory parts You'll have to deal with the reverse flow cooling and it does work better if you keep the factory EFI on it.
You'll have to deal with the reverse flow cooling and it does work better if you keep the factory EFI on it.
Le Mans Master
Joined: Jun 2004
Posts: 6,231
Likes: 65
From: Seattle WA
St. Jude Donor '14
Instructor
Joined: Mar 2010
Posts: 228
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From: Evansville WI
Last edited by Bugman Jeff; Aug 10, 2011 at 12:25 AM.
Racer
Joined: Sep 2007
Posts: 286
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From: Pensacola Fla
Back in the day before the Z 28 Camaro was around we would build a 283 bored out to four inches and built a 301 a fantastic mouse motor a lot of compression 11.5 or more high reving cam matched gearing and real gas that would make a tree hugger quiver.I am showing my age,but back the in the day thats what we did had it in my first Corvette a 59 then Chevrolet got on board with the 302 ahhh the good old school days!