Darwantae951

Hey,

I've been talking with John, Chris, and a multitude of others in regards to clutch selection and can't seem to find a good set-up that meets what I want.

My initial package was going to be a KEP2 PP with 930 disc but have heard mixed reviews in regards to not being able to fully disengage the clutch...

What are you guys using? I'd ideally like to find a disc that won't be too grabby, chattery, and fairly easy to modulate. My car is a street car which will see occasional track use at PCA events, etc...

I've seen some of you going with clutchnet sprung 6 pucks, how are these working out? What PP did you choose?

Thanks for any input guys!

-Darwin

Diver944

I have the KEP2 and 930 disk, but it is fitted to a new build engine with less than 0.2mm play in the crankshaft. I believe the problems are on older engines with excessive play.

It gives a stiffer pedal than factory but not overly so. It is very easy to modulate and is not noisy or clattery in any way. The bite point is lower than a new cup clutch (which mine replaced) but you get used to it after a few miles and then its no problem. I have 480lbft of torque at 3500rpm so needed a clutch that would GRIP TIGHT and hold on

95ONE

I just put in a 6 puck ceramic (Sprung) disk. Had clutchmasters rebuild it.(pressure plate) . held every bit of power on my 10-15 1/4 mile runs. and 3 events.. (before I tore it down to it's current state)

Pedal pressure is almost same. A lot Grabbier though. No chatter. Excellent set-up.

Love it.

rlm328

Spec 2. At 15 psi boost 340 rwhp. How much hp are you planning on putting down? A lot will depend on that.

Darwantae951

My engine will be a brand new build as well so crankshaft endplay should be very minimal.

My engine will be a 3.1L with big turbo so I would think somewhere around 450whp (I hope ).

rlm328

Here are some torque limits for various Spec Clutch stages.

PP- Pressure Plate
LW Light Weight

CLUTCH STAGE TORQUE STD/LW PP TORQUE w/ALUM PP
STAGE I 310 ft/lb 370 ft/lb
STAGE II 380 ft/lb 450 ft/lb
STAGE III HYBRID 450 ft/lb 530 ft/lb
STAGE III 6 & 4 PUCK 500 ft/lb 600 ft/lb
STAGE IV 500 ft/lb 600 ft/lb
STAGE V (DRAG) 650 ft/lb 780 ft/lb

I am sure there are other manufacturers tables out there to get you un the ball park.

With that much HP I assume you will be putting down about 500 ft-lbs torque or so. That puts you into the hybrid and puck range.

Good Luck

George D

Clutchmasters will build to suite your specs. I've used them in the past, and am now installing a newly built clutchmasters setup for my car.

The Kennedy PP and 930 disc is as good as it gets for a 350whp and under car. I put about 60K on another 330whp 951 with zero issues.

With your setup, you will slip a 930 disc unless you have some monster PP holding it in place. My clutchmasters setup is almost like stock as far as pedal pressure.

PM me if you want specifics, or simply call them. They are easy to deal with.

George

theedge

I have a KEP2 with stock disk and wouldnt get anything else.

If you want smooth, nice to drive, etc... Dont get a SPEC. Yuck.

fortysixandtwo

I'm using one that Scott Gomes spec'd out. It's a 4 puck with a sprung hub.

MPD47

George I urge you to stay away from clutchmasters. Myself and several friends and customers at the shop I used to work for had NOTHING but issues with them. I've personally seen 3 M5's (from stock to not) blow out clutch masters 6 puck clutches. Absolute garbage.

It would be nice if someone offered a nice twin plate setup for 951's. Pretty much all I'll run anymore. Great engagement, perfect holding power, and light as hell.

FWIW I ran a Spec3+ on my car with a stock flywheel when I was running 390whp+.

I'm currently running an ATS Carbon Twin Plate on the 350z, which was used on the Twin Turbo motor it used to have (PO) and I'm reusing on the Titan V8 (Vk56, modded, 400whp) I'm putting in this winter.

RolexNJ

Darwin, I know you want something that will hold, doesn't chatter, holds big big power down, and is easy to modulate? So basically you want the best of all worlds, right? J/K. I can tell you this, Special Tool made 602 RWHP & 480 TQ, I believe, and was running a Kep Stage 2 with Woody Weiss copper/ceramic 6 -puc, no springs. I heard it was a bit harsh, but God knows it held. From my personal experience with my other 3.0L, I had a Spec 3, 4-puc clutch, and I would never, ever get another Spec, but then again that is just me. My car made 460 RWHP and it held all the power down, but it chattered bad off the line, really bad in reverse too. The pedal pressure wasn't bad at all, but the chatter bugged me. I personally believe this is a natural trait of Specs.

As for my current project car, we'll be using a custom clutch that Markus Blaszak makes - he uses a Porsche center section and adds custom facing material Kevlar, fibertuff, sintered bronze, to make up a custom clutch. That along with a slightly higher clamping force pressure plate will hold a lot of power. We are going to use a Fidanza flywheel that is a steel faced aluminum flywheel, as Chris likes the throttle response from these quite a bit. With this set up, as per Markus, he states his set up will hold 600 TQ at the flywheel. It will be as smooth as possible, with no additional pedal force required. Our hydraulics can't handle additional force over an extended period. Hope this helps in conjunction to what others have recommended.

You better at least make that with a 3.1L.

2bridges

Hey there, I have found the option for me, sounds like it may be exactly what you are looking for

Spec stage3 + (part number is 293F)
NOTE: NOT stage3, or stage3 hybrid(6 puck), this is the 3+ (plus) full faced disc
Called and talked a few times with Spec techs, are knowledgeable helpful folks
here is what they advised me about the 3+
1.) EXCEPTIONAL clutch modulation(considerably better than a stage2 spec)
2.) EXCEPTIONALLY long wearing (of all spec clutches)
3.) good to 580lbs torque


Here is the manufacturer- spec's description:
The flagship stage for a high powered street or race car that requires a manageable and friendly engagement, the stage 3+ features a carbon semi-metallic full faced material that offers unparalleled life, friction co-efficient and drivability characteristics in one single package. The hub is double sprung with spring cover relieves for flexibility and heat treated components for strength and durability. Great for street, drag, drift, autocross, road racing, pulling, rallye and drift.

High clamp pressure plate
Carbon semi-metallic friction material
High torque sprung hub and disc assembly
Bearing and tool kit

________________________________________________________________________ ___________________________________________
Rolex - I believe the only 4 puck spec clutch is solid hub pure race clutch. Harsh is an understatement and especially if you have a lightened rotating assembly. However this is not a characteristic of all spec clutches, but rather the specific product you purchased. I can't image why you would expect anything different from a solid puck disc.

George D

Know that I get what you are stating. I've had clutches from many folks go out in a few K miles. Clutchmasters has worked with us to make sure that we had what we asked for, even with failures. I've had clutches from most vendors in various cars, and I'll state that they were easy to work with, and support issues.

My best clutch for these cars with under 400WHP was Kennedy and the 930 disc. Slip on this car was the issue, and Clutchmasters has been part of the R&D for this car.

They do have there reputation on the line with their new design for my 951. If it wears out like the last unit, I'll inform this list.

So far, they have been upfront, and have rebuilt everything to spec. We'll see like everything else with this build. Work in progress, and some feeling of guilt on my part. I could have just gone to www.speedfreaks.com and blown a M3 for the same money....or purchased a 993TT and worked it.

Good thing that I still get a hit running offroad. This project has kept me off the asphalt for far too long.

I'm a 951 nut, and I'm paying the coin to get this ride perfect. Just sharing the vendors that are supporting me with little money after creating their goods for this particular car.

George

333pg333

That would not be the one Darwin is looking for in my book. I bet it's great on the track but not so nice on the street.
I've had a 6 puk like 95ONE describes and I loved it too....at speed or on the track. In town, parking etc it was pretty awful. Really shook the car up, especially in reverse. I'd happily go one of these again if it was a full track car, or something more substantial again.

RolexNJ

I know many people with 'several' different set ups from Spec and all are unhappy.

Just my $.02.