My clutch started slipping under load during my last track outing, and I confirmed today that it is still happening.

I believe the clutch and flywheel on the car are stock factory bits with several years of track events and some occasional canyon driving on them. Now that I've transplanted a very stout 2.7/six in place of the modest 2.2, I'm thinking that something lighter and stronger would be a plus if not a downright necessity.

Trans is a sideshift 914/901 with short gears, 904 mainshaft, and Guard LSD, so it's very direct in how it hooks-up and transfers power.

What's the hot ticket these days? The car is 90% track-use and it's already fairly brutal to drive on the street so I don't mind tilting even more in that direction if there is a noticeable benefit and good strength/reliability.

Thanks,

not sure about the hot current ticket....

IIRC my 916-6 with 2.7 RS motor I ran a 911s clutch and a slightly lightened flywheel. That is the car shown in my current avatar...
I had trouble with slippage until I put in a new clutch disc and all was good, but required a very good adjustment to keep it from slipping...
a well built 2.7 has a ton of low end grunt

A bit of history.
Originally, I installed a Kennedy Stage I clutch set up on a stock 911 flywheel.
Never had a problem. It is still good.
Brit got all pumped up about a light set up and sprung for it.....it puked soon there after.
He got different one at WEVO and this one is holding up well to 5k launches......about the only way to launch the sucker without bogging. In fairness, he use an F 2nd gear to lunch....er....launch. If you want to go that way, talk to Hayden at WEVO.
It uses all the stock linkage except for some kinda odd ball throwout bearing.
It's not too tough on the leg but long term reliability of the linkage is in question.

Personally, I see no huge advantage in it....and it would be a disadvantage in a street driven car.....not to mention the added expense. It did drop about 15 lbs of rotating weight off the car. Weight drops is gud.

My car has the following:

1.3.0 911SC engine
2.stock flywheel
3.Kennedy Engineering stage II pressure plate and clutch disc
4.Kennedy Engineering ring gear

Clutch " feel " is great with easy engagement with little " foot power " needed.And NO SLIPPING at all ! I only have about 500 miles on this setup but so far so good.

Actually this thing is a top-end screamer but the low-end is still noticeably stronger than the previous 2.2, of course. It's slipping at 5000+ rpm's, not so much off the line.

Thanks everyone for the info thus far. I will check into the Kennedy and Wevo offerings.

I like rfuerst911sc run the Kennedy Stage II with my 3.0. Its been in over a year with a few DE's. No problems.
Van914

More history.
I did the conversion to a 2.4L back in 98.....pre internet for me. Information was available where you could find it. On the clutch, information was sketchy but a bit of info was about Kennedy. What I didn't know (amongst other stuff) was how stiff was stiffer. I went with the Stage I hoping to make the notorious linkage live as well as keeping the new motor hooked up to the rest of the driveline. In 9 years of use it never had an issue withthe clutch or linkage.....and there were 8 years of abuse.
A motor rebuild after 7 years showed the clutch/flywheel to be in superb condition so I slapped it all back in behind the rebuilt motor.
The stage II may be a better set up.

Today I finally put the car into its "streetable" trim (LOL), cleaned it up a bit and went for test drive. Now I'm not sure it is the clutch, but I can't tell what I was feeling. I drove it around the block two weekends ago it I thought I felt slippage too. But today it seemed to hook up normally. Albeit I did not hammer the throttle or shift as hard as on the track...not anxious to get arrested.

What are symptoms of an LSD that is wearing out or out of adjustment?

What I felt was almost like wheelspin, but it was at >100mph so I kinda doubt it was that...

Maybe u need my puck clutch that I am taking out in the next few weeks, it grabs perfect for a track car, but not a daily driver.