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Old 01-03-2013, 02:40 PM
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Originally Posted by thefox View Post
thanks for your info that helped alot i did forget to say that i did install a comp cam 268ex cam if that makes a difference. but if its not going to make a difference i might not bother. thanks again.
The '72 LT-1 had flat top pistons, so any large chamber head is going to give you a fairly low compression ratio (9:1 range). The best way around this is to use a smaller chamber head and a flat top piston, if possible. Unless your original pistons were replaced w/dished pistons.

I'd suggest a Vortec-type head like the small port Bow Tie vortec heads sold by GMPP. They require a Vortec specific intake but are worth a LOT more power than any production Chevy head. But a 64 cc chamber volume w/flat top pistons and a 0.040" quench distance will be about 10.4:1 CR. This is high for pump gas. So ideally you'd use a D-cup piston to get the CR to the 9.5 to 10:1 (max) range.

More here.
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