I have a 92 hatch 306, ford racing T5 and clutch with 373 posi and around 80mph it shakes pretty hard. It is only at high speed not at high Revs let me know what you think.
Thanks Tag

 

The wheels may be slightly out of balance if it does it while you are both on and off the throttle. The u-joint may be starting to go if it does it only on the throttle.

I'm sure others will have additional thoughts, too.

 

in gear or out of gear? that would answer alot.

 

My thought would be tires. Could be out of balance, or cuppage in the tire itself.

 

Take a look at tie rods. It's common with our cars after 15 or 20 years. Jack the front up and put hands and nine and three and see how much play you have.

 

my girlfriend had this problem... her wheels were not balanced, once she got them balanced it fixed the problem

 

yea does it do it in gear or out of gear or both? does it get worse when you put it in nuetral at 80

 

Does it go away if you go over 80? What does it do if you hit lets say 95 to 100? I had a similar problem and if I went over 90 it went away and then when I slowed back down it would shake again around 80 or so. It was a bent driveshaft. Just another option for you.

 

yea thats what my problem was too, the driveshaft was outta balance for me not bent though

 

how would the driveshaft get out of balance? from not re-installing it correctly or does it just go out on its own?