It really depends on how important drivability is to you. There are pleanty of single disc clutches that are puck style with a heavy pressure plate will hold over 600whp no problem. Act 6 puck or the competition stage 4 are all examples. But the drivability of these clutches will be horriable. If you drive a street car in stop and go traffic you will hate your car with theses clutches. If drivability is important you really need to go twin disc at this power level. Ideally the sos carbon on carbon twin if you want good drivability and high power holding ability.

if drivability is important I always recommend the stock clutch for 320whp and under and the act hd plate with stock disc for 330-500whp and the sos twin disc for over 500whp. If drivability is not important just go cheep and get a competition stage 4 and hold 600+whp all day with crap drivability.

 

A light weight flywheel will remove some of the clamping force duty needed from the PP, effectively broadening the window before slipping would normally occur. No one should be running the factory ap2 boat anchor if they are worried about maximizing their clutch capacity. This engine responds beautifully to 8lb flywheels anyway.

 

Competition stage 4 clutch at 545 torque for over a year now with out issues. Also have the competition lightened flywheel. I don't think it is a pain to drive.

 

I hate the the light weight flywheel with a passion. I had an ap1 and now I have an ap2. I prefer the ap2 flywheel as it smooths everything out. Before I boosted my car it was much more pleasurable to drive than the ap1 was.

 

Learn to drive smooth. The ap2 flywheel is ridiculously heavy at 22lb, its not a sports car flywheel. The rpms just hang in mid air, its not conducive for sport driving, nor making a clutch last. The 14lb flywheel in the ap1 is fine overall but I prefer lighter.

 

7.5 lb ftw.

 

600whp/450tq
hd act pp w lighter flywheel
no slip in over 4 yrs and 9k miles but I don't launch just 3/4/5 hw pulls and limited boost in 1/2

 

what?? are you sure you have a HD and not the 6 puck. I don't see how that's even possible as that clutch is only rated to a max of 370tq

 

The dyno in my signature is from an ACT full single disk, PP & Fidanza 7.5lb flywheel. Made MANY passes at full power with no slipping.

 

150% sure, just looked up my build info:
ACT Heavy Duty Street/Strip Clutch kit
ACT Streetlite Flywheel
But like I said, I don't launch the hell out of it, plus other stuff I said earlier.
FWIW, I note from my builder:
"Clutches: ACT hdss for 500whp and below.Science Of Speed (SOS) carbon twin disc for 500whp+.Both of these clutches drive amazing and do not hurt car drivability like 6 pucks or other twin disc clutches"
I'm NOT trying to trash anyone else clutch on this form or who have these clutches, just sharing some insight with you as I never drove/had ANY of the above other than original OEM and HDSS clutch & lighter flywheel.
Best of luck with whatever you choose !