09-12-2017, 07:43 AM

74Grandville 74Grandville is offline

Ultimate Warrior

Join Date: Mar 2003

Location: Plainville, CT

Posts: 1,847

Quote:

Originally Posted by 77 TRASHCAN

I calculated the compression ratio on my 1970 350 using 6 cc's dish for reliefs, .020 in hole with the 90 cc chambers, got 7.74:1. A long way from the 8.8:1 factory advertised...LOL no wonder I could run 44 degrees total timing and NOT make the thing ping. Has a 066 cam in it...

I had a stock 70 350 and cc'd the heads about the same "89cc". with the stock cam it used to pump around 135psi i think.

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1979 Firebird Trans Am 301/4spd (Now 428)
1977 Firebird Formula 400/Auto
2007 Grand Prix GXP 5.3L

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