454 Horsepower
Thread Starter
8th Gear
Joined: Oct 2012
Posts: 8
Likes: 0
454 Horsepower
Hello i just purchased a 71 corvette with a matching numbers 454 i need to rebuild the engine due to smoking and the rear seal leaking i would like to increase the horsepower but keep the outside stock meaning keep the heads and intake i was thinking about pistons to raise the comp. ratio and a roller cam if anybody has any suggestions please let know thanks
Burning Brakes
Joined: Sep 2012
Posts: 818
Likes: 0
From: coon rapids mn
try to keep the compression pump gas friendly.do a compression or leak down test first.if your cylinder bores measurements are within spec consider a mild hone and new rings. a 288 roller cam from comp cam will make good power .maybe you just need new valve guide and seals.
Melting Slicks
Joined: May 2009
Posts: 3,079
Likes: 314
2024 C3 of the Year Finalist - Unmodified
Spend your time locating a knowledgable and reputable (honest, ethical) rebuilder in your area who is willing to listen to what you want...given your budget. Regardless of the many suggestions that will be offered on this forum, it will get down to the two of you and your money. Can you do the in and out yourself?
Race Director
Joined: Sep 1999
Posts: 11,360
Likes: 382
From: Plano TX
Only so much you can do with the stock intake and exhaust manifolds. They're not good flowing pieces. Bump compression to about 9.5:1, port the heads and see if you can get the manifolds extrude honed. A mildish cam about 225/235 or maybe 230/240, hydraulic roller if you have the budget.
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
If it needs to be bored, you can get a SCAT or EAGLE rotating assembly, (crank, rods, pistons, rings and bearings, balanced) for around $2k. And that's all forged parts. You can run up to around 10:1 compression on premium pump gas if you watch your cam choice.
You're wanting to stick with the stock intake and carb- not a bad plan. Some work on them and the heads, some careful well planned choices for other parts, you'll be surprised how much HP you can make.
You're wanting to stick with the stock intake and carb- not a bad plan. Some work on them and the heads, some careful well planned choices for other parts, you'll be surprised how much HP you can make.
Burning Brakes
Joined: Sep 2012
Posts: 818
Likes: 0
From: coon rapids mn
I made 499/500 tq/hp with a blue printed stock ls6 with only a 284 duration crane solid lifter cam.consider a comp hydraulic extreme energy cam.try to create a street able dynamic compression ratio.
Race Director
Joined: Jan 2007
Posts: 14,936
Likes: 3,344
From: NYC NY
Spend your time locating a knowledgable and reputable (honest, ethical) rebuilder in your area who is willing to listen to what you want...given your budget. Regardless of the many suggestions that will be offered on this forum, it will get down to the two of you and your money. Can you do the in and out yourself?
There's an abundance of knowledge on this forum but the people helping you with advise are not doing the work. You won't get the results you're after unless you find the right rebuilder.Good luck with your project!
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