Head/compression question

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Jun 18, 2015 | 09:17 PM

rayluka

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From: Kingman AZ

Head/compression question

If I replace my factory L-48 heads with the edelbrock 60909 64 cc heads, What will this bump my compression to. I also plan to use a thin gasket. Im gonna look at a cam and want to know what I''l have to start with.

Jun 18, 2015 | 09:35 PM

Jartanyon

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From: Chicago IL

Ultimately depends on pistons, bore, deck clearance, gasket, etc, but could get you up to 9.6:1.

Jun 19, 2015 | 04:41 AM

jb78L-82

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From: Tennessee/Rhode Island

If everything is a stock L48, figure roughly 9-9.2 . Stock compression L48 was advertised as 8.5 but in reality about 8-8.3...lower for an engine with miles on it.

Jun 19, 2015 | 10:31 AM

gg521

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From: Arvada Colorado

The thickness of the head gasket depends upon quench distance. The optimum is around .040".

Jun 19, 2015 | 10:38 AM

Jartanyon

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From: Chicago IL

True. If you are using different heads and shoot for optimum quench with your gasket and deck clearance, then stock compressions will be irrelevant. When I rebuilt mine, my quench was .040" and my compression is right around 9.5 to 9.6:1. Just make sure to measure your deck clearance when the heads are off...they can vary.

Jun 19, 2015 | 03:19 PM

bluedawg

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From: anchorage ak

9 to 1

Jun 19, 2015 | 05:36 PM

rayluka

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Drifting

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From: Kingman AZ

Thanks for the info guys. So Im safe to guestimate it close to 9.5:1. I will use .040 gasket.

Jun 19, 2015 | 11:01 PM

bluedawg

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From: anchorage ak

Measure the distance the piston is in the hole, .it's probably like .025" figuring you want a total of .040" you'd want a .015" compressed thickness gasket and this would get 9.2ish to one.