85 Compression ratio
May 8, 2002 | 11:11 AM
Thread Starter
Le Mans Master
Joined: Jul 2001
Posts: 6,252
Likes: 2
From: Silicon Valley Kalifornia
85 Compression ratio
Anyone know what the the head combustion chamber volume is and what CR it yields? I thought it was 76cc's??? 9:1 CR????
May 8, 2002 | 12:41 PM
Thread Starter
Le Mans Master
Joined: Jul 2001
Posts: 6,252
Likes: 2
From: Silicon Valley Kalifornia
Re: 85 Compression ratio (GRX)
ttt
May 8, 2002 | 02:13 PM
Race Director
Joined: Aug 2000
Posts: 11,506
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From: Vancouver,Wa.
Re: 85 Compression ratio (GRX)
9-1 is correct. CC size I am not sure.
May 8, 2002 | 02:17 PM
Safety Car
Joined: Dec 1999
Posts: 4,691
Likes: 1
From: Framingham MA
Re: 85 Compression ratio (GRX)
I think they are in the 60cc's, maybe 68cc. You may want to ask the C3 group these heads 624's were used on all 78-85 Corvette.
May 8, 2002 | 04:02 PM
Le Mans Master
Joined: Feb 1999
Posts: 6,172
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From: somers, ny
Re: 85 Compression ratio (dgoodhue)
the chambers are 76cc, the valve reliefs in the pistons are 4.5cc, the head gasket is a .020 steel shim and the CR is 9:1...so you got it right!!!
May 8, 2002 | 04:04 PM
Team Owner
Joined: Apr 2001
Posts: 22,267
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From: Dallas TX
Re: 85 Compression ratio (ralph)
I think most engines are 9:1 or 9.5:1 ... unless you've got reverse cooling like the LT1 and get 10.5:1 or 10.8:1 like the LT4. 8.5:1 or so for a blown/turbo motor...
May 8, 2002 | 05:08 PM
Safety Car
Joined: Dec 1999
Posts: 4,691
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From: Framingham MA
Re: 85 Compression ratio (ralph)
Quote:
the chambers are 76cc,
Doh!!! I knew that...I had a brain freeze.
May 9, 2002 | 01:12 AM
Thread Starter
Le Mans Master
Joined: Jul 2001
Posts: 6,252
Likes: 2
From: Silicon Valley Kalifornia
Re: 85 Compression ratio (GRX)
Thank you!
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Re: 85 Compression ratio (ralph)
