King Cobra clutch & nitrous
 

I installed this clutch and it slipped badly in 1st and 2nd on the first run with the Nitrous jetted for 150hp:

1986-2001 Ford Mustang King Cobra 10.5" Stage 2 Clutch Kit - UPR-M-7560-C302 - UPR Products

I think you'd be hard pressed to find a clutch with a (single) organic lined disc that will hold a real launch with a 650hp engine, anyway I decided to give it a try.

I hit the rev limiter on launch immediately, shifted into 2nd and the shift light again came up immediately. Shut off the nitrous and coasted to a 13,1. Put the 100hp jets back in afterwards and did a couple runs with a new top speed of 123mph. Clutch grabs enough to support high elevens, but won't hold up to the torque with the 150hp jets. Still seems to run fine on the street after the trip to the track.

If the pressure plate and flywheel are still usable I'll give this disc a try:

http://www.summitracing.com/int/part...x302/overview/

I read that it is basically a Centerforce dual friction disc, and using this one with the King Cobra pressure plate is what a lot of guys did in the 90s, so Ford started to sell it under it's own name.

What do you think? Will it hold up to the abuse with nitrous and slicks?

This is a street car, and I don't want to use a high $$$ sintered racing clutch that will make the car near impossible to drive in city traffic.

Besides the problems with the nitrous the King Cobra clutch is perfect, extremely light pedal and also a real bargain.

Simon

I can tell you that I used to run the king cobra on one of my fox bodies at right around 500rwhp (roughly where you are) on a 150 shot and the clutch held just fine, even with hard launches. With your cobra being a good 500 pounds lighter, I'm actually surprised it slipped as much as you said.

Thanks for the elaborate reply.

A lot of people seem to have no problems with this clutch on 500rwhp fox bodies.

I installed it exactly as per the instructions and followed the 500 mile break in procedure. New Ford racing aluminum flywheel also.

My launch RPM is about 4500 to 5000 and I'm spraying it straight of the line. Nitrous is activated by a window switch and wot switch.

I read a lot about cheap china clutch discs on ebay, however I bought this one directly from UPR.

Car has a hydraulic clutch system, however pedal effort with the old Ford Racing HD clutch was quite noticeable.

I'll give the dual friction a try. My plan was to step up the nitrous 100-150-175hp (super powershot solenoids) in order to get used to it and dial everything in.