355 Compression Question
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355 Compression Question
Can someone tell me what my compression ratio will be with +30 4 valve relief flat top pistons and a 64 cc head the piston is sitting about 20 thou down in the hole from TDC thanks
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From: Tucson, Arizona
Car: 1987 IROC-Z Camaro
Engine: L98 5.7L TPI
Transmission: 700-R4
Axle/Gears: 3.27 BW
Re: 355 Compression Question
I don't know the math (well, I did, but forgot it) but I know that whoever computes this will also need the thickness of your head gasket.
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From: Philly, PA
Re: 355 Compression Question
Wiith a typical Fel Pro .039" composite head gasket (blue rebuilder head gasket) you'd be at 9.75:1.
With a thinner GMPP .028" composite head gasket you'd be just shy of 10:1.
With a real thin .018 steel shim head gasket you'd be at 10.3:1.
With a thinner GMPP .028" composite head gasket you'd be just shy of 10:1.
With a real thin .018 steel shim head gasket you'd be at 10.3:1.
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From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
That's assuming zero deck height, which is rarely the case with rebuilder pistons.
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From: Alberta, canada
Car: 84 Z28
Engine: carb 305
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Re: 355 Compression Question
Check out this online CR calculator http://www.csgnetwork.com/compcalc.html
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