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

Knock after rebuild

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Old 09-15-2011, 05:22 PM
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Default Knock after rebuild

So I completely rebuilt the entire bottom end. New custom grind cam, trick flow push rods, 1.6 CC NSA RR and single piece racing valves. I have a knock, not cold but only when it's warm and ready for action, ps it's running w/ open exhaust after y pipe right now. Also, I have an exhaust leak from the headers. It definately sounds like a rod knock but it has less than 100 miles on it. Any ideas? It's my LT1, all other mods are below.
Old 09-15-2011, 06:10 PM
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It is probably some valve train noise. A good way to check is get the car hooked up to a laptop with some tuning software and monitor the KR. I was hearing knock, but not getting any. I think it was just the switch from stock valvetrain to full roller, its just louder. Also, how are your headers looking vs the k member? They can make some noise at idle if they are close.
Old 09-15-2011, 06:54 PM
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Is it Stroked? after my rebuild the crank was tapping the oil pan and made it sound like a knock and scared the hell outa me.... jack it up and put rims with tires on them under all 4 wheels(hillbilly lift) and crawl around it and find out exactly where its coming from...good luck!
Old 09-15-2011, 08:29 PM
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did you prime the motor properly and do your oil changes you need to do early on? whats your oil pressure?
Old 09-17-2011, 09:21 PM
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I turned the motor over several times before starting it and the oil pressure is ok...but not as high at initial start like normal...also, the oil pressure needle seems to vibrate back and forth once warm. Its not to 500miles yet so I haven't changed it yet.
Old 09-18-2011, 12:36 AM
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No...it's not stroked. Really, I need some suggestions on things to look for that mimic a deep bottom end knock. I just can't see having a rod or main knock with 100 miles on it, paired with the fact that it only begins knocking, most prominently from the exhaust, when it warms up and the oil viscosity and flow takes on it's proper state....Hmmm, think I said that right...



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