As some of you may know, some may not , My f-body was originally one of the few Iron duke/4speed manuals. Here is my question, I paid a good friend of my fathers to do a v8 conversion for me (i was young and unsure at the time, and my fathers health wasnt good). He put in a 305/700r4 combo. Could he have used the same driveshaft for the v8 swap? The reason I am asking is because I have the same vibration problem as quite a few members on here do. starts at 65mph and gets worse as the mph goes up, it has been doing this since it was a 4 cylinder. everything has been changed (wheels tires, etc.) The driveshaft is the main thing I am looking into at this time. If the driveshaft couldve been shared, Im almost positive that an aluminium one will fix the problem. If the driveshaft could not have been used, I will look elsewhere. Thanks for all of your help

<shake> <shake>

 

4 speed manual is length and spline o the 200C and shorty th350, so he would have to find an 82 (longer)driveshaft, but since its got a 700r4 in it then he couldnt have used the original drivesahft and now you should have a hard to find longer 82 style shaft in your hands right now and a 700r/T5 shaft under car now, shaking unbalanced feeling can be caused by broken or misaligned mount or tranny(out of line driveline), or axle, or bad U joint, if itsd out of line thne thats a real bad thing for tranny bellhousing..

he didnt weld in 3" of pipe in the shaft did he ? that would be why unbalanced

 

he wouldve had to change the tranny mount too, right? whats the chances of it being misaligned for both of my old setups? could he have shared the u-joints? thats one thing that im going to check out anyways. well, i have the stock rotors and wheel bearings still on the car. 150,000 miles on the stock rotors and bearings, i think they are due (another thing im going to check out). grrrrrrrrr! its embarrassing passing people on the turnpike at 70mph and your dashboard shakes like crazy