Worth to do?
Thread Starter
Intermediate
Joined: Feb 2009
Posts: 48
Likes: 0
From: Miami FL
Worth to do?
I have a 75 L82 stock engine. These bring 333882 heads which I am told have 76cc chambers 1.94 intake and 1.5 exhaust valves. Engine is factory rated at 9.0:1 static compression.
I have a set of "double hump" chevy performance heads which are 64cc chambers, 2.02 intake and I believe 1.6 exhaust. If I simply change heads and leave the factory Q-jet and exhaust manifolds, what kind of power increase do you believe I will achive.? The car is original and unmolested....is it worth it?
Thanks for your thoughts
I have a set of "double hump" chevy performance heads which are 64cc chambers, 2.02 intake and I believe 1.6 exhaust. If I simply change heads and leave the factory Q-jet and exhaust manifolds, what kind of power increase do you believe I will achive.? The car is original and unmolested....is it worth it?
Thanks for your thoughts
Safety Car
Joined: Nov 2005
Posts: 3,961
Likes: 573
From: Lompoc, CA. Santa Barbara County
If you have a stock L-82 engine, you already have 2.02 heads. If you've found camel hump or double hump heads, check to see if they have been drilled for accessories. When my L-82 was stock, I replaced the factory 2.02 heads with Airflow Research 190cc heads. It was the biggest single improvement to the engine up to that point. The technology of modern aftermarket cnc machined aluminum heads are the way to go, unless you are on an extreme budget. Even then, I bet you can find some aluminum L-98 heads at a reasonable price. Camel hump or "fulie" heads were the hot ticket in the 60's and 70's, but you can do much better with modern heads.
Just my humble opinion. You will get more. Just wait for it.
Bee Jay
Just my humble opinion. You will get more. Just wait for it.
Bee Jay
Race Director
Joined: May 2005
Posts: 10,674
Likes: 122
From: Millington Illinois
St. Jude Donor '08-'09
Modern heads are better. That said L-82 cam likes more compression. I worked in a high performance machine shop in the mid to late 70's. The double humps were all we really had to try to get power out of. Built 500 hp motors with these before aluminum heads or roller cams. They were dedicated race engines. They can be heavily ported and flow good numbers when ported even by modern standards. On a L-82 350 they will help. Better with headers. You can get respectable power increases. Check out the flow numbers on even some of the unported versions here. The ported ones are right up with some of the modern heads.
http://users.erols.com/srweiss/tablehdc.htm#Chevy
http://users.erols.com/srweiss/tablehdc.htm#Chevy
Last edited by 63mako; Feb 18, 2009 at 12:37 AM.
