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Old 07-26-2012, 02:36 AM
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cobalt327 cobalt327 is offline
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Quote:
Originally Posted by danderduff View Post
most my friends only have 2 bbl stuff due to racing rules.

Anyways, after messing around a bit tonight i established a couple things.

I think i have internal engine issues, and driveline issues like greg t suggested. a little more history on the vehicle; i did the 700r4 trans swap into my vehicle which required the driveshaft to be shortened. We shorten driveshafts frequently on our racecars (which turn far more rpms than street vehicles) and we decided to attempt shortening one for this one and see what happens.

Well driveshaft is either bent, slightly twisted, or just has horrible runout. i had on jackstand and put in gear and could see the driveshaft go up and down. where this fits into my issue, when i hear the popping and banging going on its hard to diagnose just with sound, but could possibly be the driveshaft causing some sort of noise/issue.

When driving under light acceleration, i rarely hear any sort of problem but under heavy acceleration from a slow speed or stop, i get the nasty noise.

I ALSO decided to look into a possible engine misfire and while the vehicle was on jack stands, and running. (As stated above, i have open headers on vehicle) I watched the end of the headers and the passenger side (suspected side of any engine issues) shot flames out and popped with quick rev up of the throttle, the driver side would never shoot the flames out.

Also did the cheap quick burned valve/paper myth. held piece of paper to the end of the exhaust, and signs of burned valve it was supposedly supposed to suck back in for a moment. Showed no signs of real evidence.

If the lean misfire were to be occuring, wouldnt it affect all cylinders, or at least both sides of engine, due to how the intake is designed?

I appreciate all advise and im not neglecting any suggestions. I realize its difficult to give any direct answer when i cannot give all information needed right off hand. You guys give good information and i try to put it all to use.
Engine:

I would want to rule out a broken valve spring.

I don't know if a new cam/lifters was involved w/the rebuild but I would also want to rule out a bad cam lobe. Cam and lifter break in is more critical now than ever, given the changes to over the counter 'regular' motor oil.
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