I did a little bit of searching about the stock clutch's capabilities. About the only thing I noticed was a common theme of 295-305 RWHP.

My mods are:
M2 Style intake
ASP Medium IC
SMC Alcohol injection (100% denatured w/10 GPH nozzle)
9's all around
Megan Racing DP & MP
Racing beat dual Tip CB
Power FC/datalogit with my own tune (11.3-11.8:1 AFR (depending on boost), 12-13 degrees of timing at torque peak, 8-9 degrees of split)
PLX Wideband
Koyo
Evans NPG-R
RE 34 row oil coolers
Bling bling 26 lb 18's with 285/30's on the back
2860 lbs + 200 lbs for me

A couple weeks ago I went out to the track here in Texas and the clutch was overwhelmed on the first pass when I was running 16-16.5 psi. I turned the boost down to 12 psi then snuck up to 13.5-14.0 psi where I went 13.196@111.0 with the stock 50k clutch barely holding on a 2.10 60'.

Last night I went again to watch a friend but decided to make some passes with long cool downs in between. After an hour cool-down it went 13.05@110.0 at 13 psi with a 2.02 60'. The tach was occasionally skipping up like 150 rpm then re-grabbing during the pass.

So...that's about the norm right?

I have an ACT extreme at home in Arizona and I'll throw it in when I get home in a few weeks. I just wanted to make sure of where I stand.

 

Yes, about 300rwhp (and it's associated torque rating) is all the stock clutch can deal with.

 

My stock clutch with less than 30k on it was slipping at 275-280 rwhp....and the clutch disk looks fine sitting on the workbench at the moment.

 

You can combo it with extreme pressure plate, and it will handle more torque.
The problem is with clamping force of the stock pressure plate.

 

That's funny because I have a similar mileage clutch and there is no hint of clutch slip at 300-320 rwhp. It's been to the track quite a few times on slicks as well.

 

It's not an overnight thing. It took my clutch about a year to finally start slipping from the higher power levels. You start noticing it in the higher gears first (i.e. 4th and 5th).

 

Mine has over 1000 miles of track (road course, not drag strip) driving....thousands of near redline shifts on it...

Mine does not slip in higher gears or from a roll but it does not grip in 1st during a hard launch, which I hardly ever do anyway.

 

Yep Rxman720b is using a stock disc with his ACT clutch and has no slippage with his 20b making around 470rwhp.