lt1 valve hitting piston

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Oct 25, 2009 | 01:35 PM

Burning Rubber

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From: edgewater, maryland

lt1 valve hitting piston

i just tried to adjust the valves on my new heads/cam lt1 and when i went to turn it over i can hear the valve hit the piston. I cant understand why. It has trick flow gen x heads/10.5to1 keith black pistons/5.7 h beams/CC306 cam/mr gasket mls head gaskets/7.2 inch push rods and 1.6 roller rockers.
the only things that are different from the old motor are the heads/connecting rods/pistons. everything else is the same. Anyone else ever have this problem?

Oct 25, 2009 | 01:51 PM

James Montigny

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Unless the cam timing is way off or the pistons in backwards, you should not be having P/V issues in an LT1.

Oct 25, 2009 | 01:58 PM

Burning Rubber

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From: edgewater, maryland

Thats what I thought. I have never heard of anyone having this problem but the pistons are in correctly and the cam timing is correct.

Oct 25, 2009 | 02:09 PM

fleetmgr

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Have you checked to see if it does it with all cylinders, or only one? Maybe a mislocated wristpin?

Oct 25, 2009 | 02:59 PM

Burning Rubber

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no I havent checked any other cylinders yet.

Oct 25, 2009 | 03:54 PM

Burning Rubber

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I am wondering what would be the best way to fix the problem. Should I change back to 1.5 rockers or get a thicker head gasket?

Oct 25, 2009 | 04:07 PM

James Montigny

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Quote:

Originally Posted by Burning Rubber

I am wondering what would be the best way to fix the problem. Should I change back to 1.5 rockers or get a thicker head gasket?

That's a bandaid ... find out why it's hitting. Something is wrong somewhere.
Did you happen to measure deck height when you built the motor?
Are those pistons designed for the crank you are using?