454 performance #@!###
Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
Using CR calc by Federal Mogul (aka trw/speedpro):
http://www.21cgt.com/FMWebCatalog/frmConversion4.aspx
and a FP1037 gasket @ 10.5cc, and STOCK deck clearance of 0.025" with that H581P30 piston with dome volume of +33cc ... bore 4.280" x 4" stroke ... and 119cc chamber ... I calc kessler's SCR at 10.21:1.
Otherwise same but w/ 113.06cc chamber, I see 10.78:1.
119cc w/ 0.020" deck clearance ... 10.32:1.
113.06cc w/ 0.020" deck ... 10.9:1.
If kessler's deck has been cut as little as 0.009" (0.016" deck clearance) ... and/or using a gasket w/ less volume than FP1037 ... he could very well be at or above 11:1 scr.
http://www.21cgt.com/FMWebCatalog/frmConversion4.aspx
and a FP1037 gasket @ 10.5cc, and STOCK deck clearance of 0.025" with that H581P30 piston with dome volume of +33cc ... bore 4.280" x 4" stroke ... and 119cc chamber ... I calc kessler's SCR at 10.21:1.
Otherwise same but w/ 113.06cc chamber, I see 10.78:1.
119cc w/ 0.020" deck clearance ... 10.32:1.
113.06cc w/ 0.020" deck ... 10.9:1.
If kessler's deck has been cut as little as 0.009" (0.016" deck clearance) ... and/or using a gasket w/ less volume than FP1037 ... he could very well be at or above 11:1 scr.
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
I bought a 1971 454 LS5 project car last year. The engine was rebuild by the previous owner. He stated that the engine was beefed up a little. At the time of purchase the engine did not run due to no carb, radiator or wiring. I have been putting the car back together and should get my body back from the paint shop soon. Before the body goes back on I want to ensure the engine is ready to go. I wanted to exchange the stock manifold for a perormer 2.0. In dioing this I found out that the car has:
1) Ported intake and heads.
2) H581P high performace pistons-domed with 11:1 compression. .30 over
3) pwr max hydr cam. 133802. 222/234@.050"
4) stock quadrajet carb
The guy at the engine shop said that this car would/should have a holley 750 CFM (at least) installed and needs High octane gas. My question is-- I want a car I can drive around on weekends and am not overly concerned with HP. Is this car set up for racing??? Can I keep the pistons and cam shaft in it and use it as a driver or should I change them out to more stock ones??
Thanks
1) Ported intake and heads.
2) H581P high performace pistons-domed with 11:1 compression. .30 over
3) pwr max hydr cam. 133802. 222/234@.050"
4) stock quadrajet carb
The guy at the engine shop said that this car would/should have a holley 750 CFM (at least) installed and needs High octane gas. My question is-- I want a car I can drive around on weekends and am not overly concerned with HP. Is this car set up for racing??? Can I keep the pistons and cam shaft in it and use it as a driver or should I change them out to more stock ones??
Thanks
Your compression dictates the required cam. If you have a true 10 - 10.5 with iron heads your going to need a high 230's intake duration to keep from running higher octane than pump gas. I had detonation problems with my true 11.2 aluminum head motor with a 232/240 roller cam.
I believe in smaller carbs and drivability over the loss a few high rpm hp. I use a 750 Demon on my 427. Most people racing 454+ ci motors use 850 - 1000+ cfm. My co-worker has a 496 ci motor and he runs a 500 cfm NASCAR type race carb to aid traction
Last edited by gkull; Dec 21, 2006 at 12:25 PM.
Safety Car
Joined: Aug 2000
Posts: 3,909
Likes: 26
From: Clymer PA
The camshaft you have is too small for an 11:1 motor. I run a Comp Cams 294 solid flat tappet 250 @ .050" .595/.595 and it's too small. If you are running iron heads you are going to have detonation issues for sure. You don't have enough camshaft to help bleed off the compression. I run aluminum heads, 294S and 11:1 with my 454 and I do not have any pinging with 92/93 octane.
Advanced
Joined: Aug 2006
Posts: 50
Likes: 0
Yeah the smell of that gas smelled like lighter fluid when it was being poured in.. I remember one night I was pouring it into the tank and I spilled a little on the ground where some oil was and it turned the concrete white lol. That car's exhaust smelled like you were burning wood chips when it was running. That was some fun times.. cleaned the hell out of the engine to..
Race Director
Joined: Feb 2003
Posts: 13,238
Likes: 1,092
From: YANKEES UNIVERSE 70 454-LS5 500 ft-lbs Torque
You need to figure out what heads you have. What number are they? If they are 101cc units you can get a set of open chamber heads to lower the compression some. Use the thickest gasket you can find.
You can also get more camshaft to help bleed off pressure at lower RPM's. Something with about 240 degrees intake duration at .050" lift should help.
The Rochester carburetor is a 750 CFM unit of superior design. No reason to change it.
BigBlockk
Later.....
You can also get more camshaft to help bleed off pressure at lower RPM's. Something with about 240 degrees intake duration at .050" lift should help.
The Rochester carburetor is a 750 CFM unit of superior design. No reason to change it.
BigBlockk
Later.....
