Combustion chamber L98
Le Mans Master
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From: Fort Worth Texas
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Re: (Cratzy)
So if I want to upgrade to a pair of AFR I need to change pistons, that is my conclusion?
I wouldn't.... if you get the same cc heads from AFR you should be fine. Your car came with 58cc heads, get 58cc AFR's and keep everything else the same.
Thread Starter
Racer
Joined: Sep 2000
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Re: (Marcho Polo)
I wouldn't.... if you get the same cc heads from AFR you should be fine. Your car came with 58cc heads, get 58cc AFR's and keep everything else the same.
I didn't know they had any 58cc heads, it seems that I can only find heads with 64cc or more. But that was good news, now I don't have to worry about that anymore :D :D
:cheers:
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Re: (Cratzy)
AFR does not offer a 190 in a 58cc head, you will have to get the 68cc or 74cc head. You dont have to change pistons, your compression will change from stock though.
with a 68cc head, say you want a 10.5:1 ratio, you will need a .038" head gasket and you will need a flat top (0 cc) piston. A dished piston would lower the static compression a little, but it would be around 9-10:1. So you do not really have to change your pistons.
with the 74cc head, you want the similar ratio, same head gasket, you will need a piston with (+3cc or thereabouts)
I dont know the cc of the stock pistons, anybody know for his year?
with a 68cc head, say you want a 10.5:1 ratio, you will need a .038" head gasket and you will need a flat top (0 cc) piston. A dished piston would lower the static compression a little, but it would be around 9-10:1. So you do not really have to change your pistons.
with the 74cc head, you want the similar ratio, same head gasket, you will need a piston with (+3cc or thereabouts)
I dont know the cc of the stock pistons, anybody know for his year?
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From: South River, NJ
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Re: Combustion chamber L98 (Cratzy)
I am pretty sure the data is as follows:
F-Body L98
Cast Iron heads
62cc
9.3:1 compression
Corvette L98
Aluminum heads
58cc
10:1 compression
[Modified by L98IROCZ89, 6:37 PM 9/11/2002]
F-Body L98
Cast Iron heads
62cc
9.3:1 compression
Corvette L98
Aluminum heads
58cc
10:1 compression
[Modified by L98IROCZ89, 6:37 PM 9/11/2002]
Le Mans Master
Joined: Mar 1999
Posts: 9,663
Likes: 1,682
From: Fort Worth Texas
2024 Corvette of the Year Finalist - Unmodified
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2020 Corvette of the Year Finalist (stock)
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Former Moderator
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Re: (vader86)
AFR does not offer a 190 in a 58cc head, you will have to get the 68cc or 74cc head. You dont have to change pistons, your compression will change from stock though.
I was looking at AFR's quite a bit when I had my '85 because I wanted to dump the iron heads. They were 76cc and I think going to 64cc would have bumped the compression on the '85 really good!
