How much will heads raise comp ratio?
Thread Starter
Instructor
Joined: Jan 2009
Posts: 117
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How much will heads raise comp ratio?
Hi people,
I have a 77 L82 and am thinking about fitting a set of Edlebrock Performer RPM heads.
Correct me if Im wrong, my standard heads are 76cc with a standard compression of 9.5:1 (or is it 9.0:1)
The heads I will be looking to fit are 64cc.
Any ideas on how much the comp ratio will raise with the 12cc difference?
Thanks In Advance,
Lester
I have a 77 L82 and am thinking about fitting a set of Edlebrock Performer RPM heads.
Correct me if Im wrong, my standard heads are 76cc with a standard compression of 9.5:1 (or is it 9.0:1)
The heads I will be looking to fit are 64cc.
Any ideas on how much the comp ratio will raise with the 12cc difference?
Thanks In Advance,
Lester
Melting Slicks
Joined: Apr 2002
Posts: 2,337
Likes: 14
From: Norfolk VA
Your engine uses the same camshaft (L46) 350/350. i I think the pistons are the same as the 350/300 engine. Your heads will increase it to about 10.00:1. I have the Edel RPM 64cc heads and the same flat-top pistons as the L-82 as well as the aforementioned cam. Others will correct me if i'm wrong.
Last edited by Oldguard 7; Feb 13, 2009 at 05:36 PM.
Le Mans Master
Joined: Apr 2006
Posts: 5,403
Likes: 95
bore 4.00
stroke 3.48
head cc 76
valve notchs cc 6cc
head gasket .018
piston down .026
Compression 8.87
bore 4.00
stroke 3.48
head cc 64
valve notch 6 cc
head gasket .018
piston down .026
Compression 10.06
.018 is what I have seen listed for factory steel shim gaskets.
anyway you should see a little over a point comp.
stroke 3.48
head cc 76
valve notchs cc 6cc
head gasket .018
piston down .026
Compression 8.87
bore 4.00
stroke 3.48
head cc 64
valve notch 6 cc
head gasket .018
piston down .026
Compression 10.06
.018 is what I have seen listed for factory steel shim gaskets.
anyway you should see a little over a point comp.
Last edited by Little Mouse; Feb 13, 2009 at 08:25 PM.
