RAM Powergrip, anyone used one?
 

I have a '66 Mustang with a built 289 and a 4-speed tranny. A couple years ago I somehow managed to rip all the friction material off one side of my Centerforce Dual Friction clutch. I'm still not sure how I did it, but I did not want to replace it with another Centerforce. So I bought a RAM Powergrip. In their ads they say that:

"Because the Powergrip disc provides increased holding power by using a higher coefficient of friction material, some chatter may occur."

After I drive my car for a while especially around town with lots of stopping and starting, the clutch will begin to "chatter" when I let the pedal out. I have trouble calling what I am feeling a "chatter" when it is rather violent and shakes the whole car, kinda like really bad wheel hop. Is this the "chatter" they are talking about, or is something screwed up? Has anyone used one of these clutches? Is there anything I could have improperly adjusted to cause this?

Thanks

Jeff

I would suggest calling RAM and asking them if this is their definition of chatter ;)