plese help me
 

ive got a 96 z28 and im not havin tha best of luck with this car. i recently threw my drive shaft out goin pretty fast! ive replaced the drive shaft,and new u joints and all that but ever since i put the new driveshaft on the car will shake like crazy starting off, it quits as soon as im off the clutch. ive been told that my fly wheel is warped but it wasnt before i put the new drive shaft in so im not sure. if anyone can help or give any suggestions please do.

Check your motor and trans mounts for damage.
A posi rear going bad can shake like that too and will be noticeable going around corners.

I would check the alignment between the driveline and the rear end, one of my friends took his 97 up to about 95 took and turn and when to downshift and went to second instead of 4th and had blew his clutch into pieces and when it did this it torqued hard enough that it bent the mounts on his rear end and threw the alignment off, made his car vibrate at high rpms and any speed above like 55 if i remember right.

your alignment of you car wheels might be off. check for that

thanks for the response, thats not something ive considered yet. i thought that it might be the sway bar or the trany mounts. the mounts look ok but the sway bar seems to be a little out of wack i wondered if that could possibly cause my problem, im really suprised everything looked as good as it did considering how fast i was goin. i was gonna try to take the sway bar off and see if i had the feedback but ill definitly look into your advice thanks..

possibly the tranny mounts, had a bad tail mount on my 86 did somethin like that, but not the sway bar.

I'm curious what you mean by "threw my driveshaft out"?
Did you blow a u-joint and the driveshaft was flopping around like a fish?
Did you pole-vault the car?
Or did it just come loose and slip right out?
There could have been a whole lot of whacking going on, under your car.

well both of my u joints did break, im pretty sure the back u joint broke first and then the front. i was goin about 130 mph when it happened, i didnt even know it at first because the air bags came out, but yeah there was quite a bit of whacking goin on im certain. it doesnt seem to be very much visual damage under the car but i know it took a good beating, the drive shaft was wrinkled and bent at a hard angle. from the way it looked it seems like the drive shaft should have come through the floor board. ive had the car on jack stands and put it in gear and give it some gas, and when the car isnt supporting its self there is no shaking. so thats why i ask about the sway bar, but as you can see someone mentioned the rear end mounts. im not sure what it could be ive never had this sort of problem.

i would say clutch/pressure plate is damaged. must have taken some major shock when the shaft went.

You may have bent the output shaft on the transmission.