What should the cranking compression be?

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11-14-2009, 09:52 AM

No Juice

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What should the cranking compression be?

Motor is a 402 with TrickFlow 225's 61cc, 10cc dish pistons, about 11:1 compression, VRX5 cam (236/238 601/605 113) and a Fast 92

Its only reading at about 145-150psi cranking compression right now.

What is it suppose to be?

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11-14-2009, 10:20 AM

Phil99vette

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Higher than that. My old corvette was 220s with the big cam/high compression and I think 205-210 with the 11.0:1 setup.

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11-14-2009, 10:40 AM

Bandit28

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I never saw more than 170psi on my 11:1 402

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11-14-2009, 01:18 PM

SweetS10V8

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I wouldnt worry about the number, as long as they are all within the same range.

Are you down on power? Whats the problem other than its not the cranking compression you thought you should have?