Well anyone that really knows have an answer? I'm not looking for a guess or I think's, just posts from someone who REALLY knows what it is, the cause, and fix(s). Thanks!
Clutch Chatter is a lot like wheel hop inside of your transmission. I put a stiff clutch with a Kelvar disk in my 98, and if I was midly aggressive on the gas when starting out, it would chatter. It was the clutch grabbing, then bouncing off of the flywheel (similar to wheel hop). Put a Spec Stage 3 clutch in a street car, then try to takeoff smoothly at 1,500 rpm. You'll feel it pretty bad. I found that either a very light touch on the gas, or an aggressive rev then dump would prevent the chatter, (although the aggressive rev then dump would light up the back tires).
A clutch misaligned relative to the flywheel can also chatter.
I disagree that all Cobras have chatter. I think it is caused by improper clutch breakin, oftern BEFORE you ever receive your car. Some of the clutch material gets glazed or deposited on the flywheel. My clutch has no chatter, and a lot of other guys I know have no chatter.
Sometimes it goes away with time, if you're lucky.