When I hit the Perc and add throttel there is a clunck in the clutch is that normal?

apperently so ,i just added perc,and have the same noise,by buddy has factory perc same clunk,
nature of the beast

Our sleds do the same...sounds like there is something broken in there...

Yes, it's normal. It's just the rollers shifting from the forward ramp to the reverse ramp or the other way around. As long as you don't hammer the throttle real hard (shouldn't do it with any reverse) there should be no problem.