Engine vibration.
 

Hey guys few quick questions. I got a Nasty vibration in the car right under 3000 rpm and up to any where from 4500 to 5000 ba enough to scramble an egg. At first I thought tires but I balanced them and made no difference. Then I noticed that if I am parked and in neutral slowly bring up the rpm it starts to shake so I know it's not a wheel tire o tart end problem. I have come to a few possible conclusions. 1. When I put the balancer back on I didn't have cylinder 1 at tdc compression. 2. I had the flywheel machined maybe that's off a hair. 3. I did swap cranks when I built the motor and it now I realize that the crank I put in was from an automatic and I have a stick could that be a problem? I am looking at a new balancer that is keyed so I know it's on right. Any info or ideas would help thanks.

Personally I would check the balancer first, is it a stock unit?

Yup.

balancer is zero balance. flywheel is "400" balance. and if the high spot(off balance) spot of the clutch pressure plate isnt lined up with the high spot of the flywheel they zero out and the motor will vibrate like CRAZY! and its not good for the rod bearings. hate to say it but with out the stock yellow paint mark on the flywheel and yellow dot on the pressure plate they will have to be re balanced together.

Yea I don't recall lining up the pressure late with anything when I put it in so that could be a problem. That's y I asked thanks for the info.

the pressure plate is supposed to be zero balanced

I don't recall any info in the clutch package regarding indexing it to te flywheel. I could have missed it.

Spec has it in there paper work. Pressure plate on the lt1 is Not zero. there was a yellow dab on the blue paint near one of the bolt flanges. Some guys say use the dowel pin hole as a reference but i never had good luck with that. just had em balanced together.

http://www.camaroz28.com/forums/driv...-plate-663827/ some pictures.

I read through that tread and pg 3 guy talks about spec stage 2 says its balanced. That's the one I have and if thts true then it shouldn't matter where it's mounted in relation to the flywheel. But if the flywheel isn't neutral it would matter in relation to the crank.

i guess its time to read the install sheet that came with your clutch? mine sed make sure to index it. meaning its Not zero balanced. But balanced for the counter weight the rear of the crank needs.