LT1-LT4 Modifications 1993-97 Gen II Small Block V8

signs of a bad valve?

Old 01-03-2013, 09:39 PM
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Default signs of a bad valve?

I'm going to go look at a LT1 trans am. And the guy I'm going to be getting it from says that it has a "bent valve". When I go look at this car what signs chould I look for to know its a bad valve. He says it backfires quiet a bit when you rev it up. He thinks that the valve is sticking. What are some possible signs. Any tips will help me! Thank you!!
Old 01-03-2013, 10:17 PM
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running like ****.

compression test will be needed to determine the exact problem
Old 01-04-2013, 07:31 AM
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bent intake will pop through the intake, bent exhaust will pop through the exhaust.......as said above do a compression test it will be down dramatically look for 70-100psi on that cylinder or less........
Old 01-04-2013, 02:10 PM
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If its stock good freaking luck doing a compression test, better bring someone with super skinny arms and tiny hands
Old 01-04-2013, 05:14 PM
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The pop out the intake or exhaust constantly will be the best indicator. Dont run it too long though, a bend is followed shortly by a break.
Old 01-04-2013, 06:04 PM
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old school test is get a good sheet of paper like cardboard paper and put it to the exhaust. Lay it on there while its running and if it get sucked in then there is a bent valve.
It should stay flapping outward the entire time.
Old 01-05-2013, 08:33 AM
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Originally Posted by robsquikz28
old school test is get a good sheet of paper like cardboard paper and put it to the exhaust. Lay it on there while its running and if it get sucked in then there is a bent valve.
It should stay flapping outward the entire time.
I have heard this is a pretty inaccurate test since every car experiences some sort of reversion to some degree.


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