poorb0yw

Hey guys,
Well after searching the various boards of Rennlist (not just the 993 forum) I've come up short in finding any information on clutches other than the RS or GT2 versions. My current stock clutch is about to go and I figured I might as well put something in to hold future upgrades I was planning.

My question is, what would be a good clutch to hold approx 420-450 hp to the ground? I'm pretty confident in the RS versions inability to do this with a reasonable life span. Also from what I have read about the GT2 clutches, they still require some modification to hold power and last more than 5-7k miles.

Also I was interested in a Tilton Carbon/Carbon setup but haven't found much information on the web about this either. Do they make a setup for the 993?

The car is driven approx 3 days of the week. A stiff setup shouldn't be a problem to deal with since there is another car to tackle bumper to bumper traffic duty.

Greg Fishman

Stay with the RS version unless you want a clutch that is hard to live with. I have a race clutch in my car and I wouldn't want to use it everyday.

poorb0yw

Hi Greg,
Which clutch do you have in your race car (happen to know the torque or NM rating for it?)?
Is the RS clutch up to the task of holding high power numbers?

JC in NY

Racing clutchs are puck type and they do not slip, so you will grow to hate it for street use.

Greg Fishman

Like JC said the puck style are not streetable. I have a clutch out of Larry Schumacher's 993 GT2 which made close to 700hp I think. It grabs very hard and I have all of about an inch of clutch travel. Zero slip what so ever with my measely 286hp.
In slick conditions I have to be especially smooth with up and downshifts due to the extreme lock up. I did a slow up-shift and the revs didn't match well at Mid Ohio in damp conditions and had the back end step out once I let off the clutch while in 4th gear. Not fun, and I changed my technique quickly.

What kind of HP#'s are you looking at? My guess is the RS or Turbo (not sure if they are one in the same) clutch with the RS flywheel will be fine for most applications. I am sure you could spend more money but it may not be neccesary.

N105DVV

RS clutch is good for 50K miles, with the standard 300hp engine. RSR/clubsport clutch, which i have now, is more robust but not as streetable as mentioned. Can be a PITA in crawling traffic. But i live with it. <img border="0" title="" alt="[Wink]" src="wink.gif" />

poorb0yw

I'm looking for something to hold approx 530 hp at the crank when all is said and done.

Greg- is the clutch from the GT2 modified in any way or is it the standard issue for the race cars?
When you say there is only about an inch of travel are you referring to total pedal movement or just a one inch zone within the normal clutch travel in which the clutch engages? Happen to know if its an organic plate or sintered disc setup?

Anyone know anything about whats available from Tilton?

Thanks again guys

Greg Fishman

Princeton,
I don't think the clutch was modified in any way. The pedal travels the normal distance but only about an inch or so is useful. The release and take up are right at the top of the travel. Not sure what you mean by organic or sintered.

Maybe Steve W. can give you some info on the Tilton clutch, I remember him posting some info a while back about a very lightweight clutch/flywheel option. It wasn't cheap.

E. J. - 993 Alumni

Princeton, take it from me, you DO NOT want the clutch in Greg's race car in your street car. I have driven his race car and once I made it out of the pits it was a great experience. But smooth shifting would have taken me about a week to figure out - almost as long as it took me to get out of the pits.

E. J.

Greg Fishman

EJ did pretty good in my car. I only think he stalled it four or five times.

Another friend drove it for some parade laps at Road Atlanta and he got stopped on the up-ramp out of the pits and after a half dozen tries we had to change seats.

I rev it to 3-4K rpms so I don't stall it, which is especially embarassing during pit out before a race. Makes the pit out workers laugh though...

TB993tt

</font><blockquote><font size="1" face="Verdana,Tahoma,Helvetica">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Helvetica">Originally posted by poorb0yw:
<strong>I'm looking for something to hold approx 530 hp at the crank when all is said and done.
</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">It is not high hp that will determine if your clutch slips but high torque. The GT2 organic road clutch will hold up to around 690NM or 507lb/ft (incidently, if that 530hp is produced at 5500rpm then that is around 507lb/ft at that point)
If you need to hold in excess of 700NM (515lb/ft) I can reccommend a set up from FVD which utilises a modified GT2 pressure plate and organic disc which seems able to hold up to 800NM and is as easy as stock to use in traffic.

Arthur Del Mundo

OK when I bought my car, the previous owner stated it was an "RSR/GT2 Clutch and Pressure Plate". Is that the puck type clutch which Greg Fishman mentions that he has or is it another kind of clutch?

kev

Arthur,

I just installed a RSR/GT2 clutch, PP, and RSR LWF into my car and I drive it on the street to and from the track without issue. I believe the clutch and PP were 964 part #'s and not puck-style. Greg?

Greg Fishman

Kevin,

I am at the end of my knowledge here, but I wonder if what you got was the RS flywheel/clutch package, similar to what Gert sells. What was the price/ part #'s. I would think the RSR clutch/flywheel would not be very streetable. I drove a factory RSR race car and the clutch feel was very similar to mine.

<a href="http://www.carnewal-europe.com/cpx_p93059.htm" target="_blank">http://www.carnewal-europe.com/cpx_p93059.htm</a>

Picture of the RS Clutch here: <a href="http://www.carnewal-europe.com/cpx_p93076.htm" target="_blank">http://www.carnewal-europe.com/cpx_p93076.htm</a>

This is similar to what my race clutch looks like:
<img src="http://boards.rennlist.com/upload/clutch.jpg" alt=" - " />

Look towards the bottom of this page :

<a href="http://www.hartmann-motorsports.com/porsche.htm" target="_blank">http://www.hartmann-motorsports.com/porsche.htm</a>

kev

Greg,

I only looked at the parts that went into my car for a few minutes, but I don't recall the clutch resembling your race clutch. My setup is from Andial: a "RSR/GT2" pressure plate, "RSR/GT2" clutch, and RSR flywheel. The part #'s are 964 116 028 53 (pressure plate) and 964 116 011 61 (clutch). I'm PET-less, so I can't verify these. The flywheel is an Andial part, but I was able to weight it before it went into my car and I believe it is an RSR spec flywheel since it only weighed 11# versus 19# for the RS flywheel.