Thread: 327 rebuild

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I just found some 14014416 heads off a 305. they're 58cc according to chevy casting #'s url. I calculate 10.86 compr ratio if I use a gasket that crushes to .043 and a .010"' deck clearance. the vales r 1.84 intake. am I headed for trouble with pump gas?

IMO yep. You might get away with 10.86 and premium ethanol blend with aluminum heads, but I'd say iron heads are going to be detonating if you push the timing.

Originally Posted by ecreek

I just found some 14014416 heads off a 305. they're 58cc according to chevy casting #'s url. I calculate 10.86 compr ratio if I use a gasket that crushes to .043 and a .010"' deck clearance. the vales r 1.84 intake. am I headed for trouble with pump gas?

I don't understand why you're being so hard-headed about this static compression ratio thing. Max 9.5 for iron heads. Max 10.5 for aluminum heads. Each point only allows the motor to make 4% more power, so taking a 300 horsepower 9:1 motor to 10:1 will make an additional 12 horsepower. That's it. That's the awful truth. Keep your street motor at 9.5 or less for pump gas and iron heads.

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