Did you replace both the disc and pressure plate with 11"?

I've only run into this once on my 63. The flywheel was heat checked. IIRC you could see tiny cracks and blued metal around them. The machine shop had to make several passes to clean the face of the flywheel. I wouldn't say mine was violent and it would disappear with more RPMs.

Larry


I don't own a vehicle that isn't old enough to drink.