Factory Heads

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Feb 18, 2005 | 09:46 PM

formula_novice

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From: St. Louis, Missouri

Car: 1989 Firebird Formula

Engine: 383 Stealth Ram

Transmission: 700R4

Axle/Gears: 3.73 9 bolt Posi

Factory Heads

Can anyone tell me the specs on the 1989 factory L98 (non-corvette) heads?

For example, 64cc combustion chambers / 180cc intake runners?
I assume they are not 2.02" int valves?

I am looking at getting new heads and would like to know this info so I can estimate my compression ratio.

Thank you!

Feb 19, 2005 | 10:03 AM

DeepSouth_454

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From: Catching Up

The 64cc for an iron L98 head is all you need to calculate the compression ratio.

Feb 19, 2005 | 10:11 AM

Black 91 Z28

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Joined: Oct 2001

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From: Starkville, MS

Car: 1991 Camaro Z28

Engine: 350

Transmission: 700R4

Valves are 1.94 In and 1.50 Ex. The chamber is 64cc and I think the runner is somewhere in the 160-170cc range but I'm not 100% sure on the runner size.

All you'll need to know for the compression ratio, atleast from the head, is the combustion chamber size.