gnosis

Can anyone advise whether it's possible to mate a SPEC Stage 1 or Stage 2 clutch kit to a Fidanza lightweight flywheel? I've heard that spring centred clutch plates won't work with Fidanza flywheels, and that some combinations of pressure plate and Fidanza flywheel cause vibrations around 2500rpm. Any info appreciated before I part with my money.

I'm particularly interested in hearing from people who are using the Fidanza flywheel in their 968s themselves.

Clayton

RajDatta

Clayton, Spec also sells flywheels. Why mix and match and not go with the same vendor for everything? It would eliminate any possibilties of finger pointing if things don't work.
Regards.

josephsc

Clayton,

I was going to reply to your PM, but my message was too long, so I figure I'd just reply to your PM here.

My experience with the Fidanza flywheel has been lukewarm -- neither ecstatics nor unsatisfied. I've only driven the car for 5000miles, but no problems thus far, except for the annoying vibration at 2300rpm -- and this only happens when I'm going at precisely 15mph (ie slow city driving or freeway traffic). Actually, I don't mind it as much as the fact that it always freaks out the passenger.

In hindsight, if the car was my daily driver and if I still lived in LA, I would have preferred my old dual mass flywheel (it was more comfortable). But, the car is really more my weekend driver so the vibration is just a minor nuisance. The advantages are the faster spool up (I can definitely tell the difference) and lower cost.

Your experience may differ depending on how it's installed. I know someone on 968.net has reported that the problem can be solved if the flywheel is properly balanced prior to installation -- but that is a new piece of information and I'd like to hear a second opinion given the source of the information. Interestingly, I also have a 968 engine mated to a 944S2 flywheel (still a single-mass but I think its slightly heavier than Fidanza) with no vibration -- and installed by a different mechanic. But then again, a bunch of people on the BMW side also report vibration problems. So who know?

BTW, both my 968 and my 944 (the one with the 944S2 flywheel and 968 engine) have spring-type Sachs clutch. The 968 -- the one that vibrates -- also has a stronger pressure plate.

No real answers, but that's been my overall experience -- bit of a nuisance, but maybe there's a solution.

Cheers!

RajDatta

Joe, interesting to see that you were able to find a spring loaded clutch plate for the fidanza unit on your 968. Funny thing is that the vibration is still there. Just wondering if the housing itself or the slide mechanism on the torque tube has something to do with the vibration.
Joe, let me know if you are upto discussing this sometime over the phone.
Raj

BruceWard

David at Specclutch.com told me that he could balance the flywheel and pressure plate together as "flash over at 968.net" suggests should be done to avoud that 2300 rpm vibrations. I have little trust for flashes opinion, but if you call spec he will offer a package price that is much cheaper than buying the Fidanza and the Spec clutch. He also suggested that he could provide slightly heavier or much lighter custom flywheels.

RajDatta

Bruce, I would say, stay as close to a 944S2 flywheel weight as you can cause you know that works with a similar trigger setup without any vibrations. I was in your shoes, I would just source all 944S2 parts and get rid of the 968 setup all together. Ofcourse, this way you will lose the ability to do 2 hr clutch changes and turn them into 20 hr changes. The upside is no vibration or DMF failure ever. Clutches are normally 100K items so I am not worried about losing 2 hr clutch change setup.
Raj

BruceWard

Raj, I had wondered if it was possible to use a S2 flywheel. I have the box of parts from Zims sitting here in my living room. So tomorrow the DMF and stock 968 parts are going back on. I called a local mechanic who makes house calls, he also happens to be the president of our local PCA and he is going to come and help with the reassembly. I figure that with $700 of parts I might as well pay a little more to make sure they are put on correctly.

Hopefully, my 968 will be back on the road and going stronger than ever tomorrow night.

I spoke to Ninemeister about the single mass Porsche Motorsport flywheel that he had planned to copy. He said that it would take about six weeks but if anyone wanted to order one of them he could have them made for less than the cost of a DMF. I do not feel like I can wait 6 weeks for it, but this one sounds very interesting. I think it should be close to stock weight and single mass. Raj, I assume you may know a lot more about this one than I do. Ninemeister bought the last new one from the factory and took measurements to be able to produce them.

BruceWard

Raj, I had wondered if it was possible to use a S2 flywheel. I have the box of parts from Zims sitting here in my living room. So tomorrow the DMF and stock 968 parts are going back on. I called a local mechanic who makes house calls, he also happens to be the president of our local PCA and he is going to come and help with the reassembly. I figure that with $700 of parts I might as well pay a little more to make sure they are put on correctly.

Hopefully, my 968 will be back on the road and going stronger than ever tomorrow night.

I spoke to Ninemeister about the single mass Porsche Motorsport flywheel that he had planned to copy. He said that it would take about six weeks but if anyone wanted to order one of them he could have them made for less than the cost of a DMF. I do not feel like I can wait 6 weeks for it, but this one sounds very interesting. I think it should be close to stock weight and single mass. Raj, I assume you may know a lot more about this one than I do. Ninemeister bought the last new one from the factory and took measurements to be able to produce them.

RajDatta

Bruce, interesting that you were told that about the motorsports flywheel. Some questions you need to ask them:
Does it fit 968 bell housing?
Does it use 968 triggers?
Does it use a spring loaded or a 1 piece clutch disk.
You might be surprised by the answers.
Raj

BruceWard

Actually I called and asked Ninemeister (Colin) about it. I did not ask any of those questions but I assumed it was a factory part that swapped out with the DMF.

I assume that from your turbo experience you know the answers and that it is not an easy fit. Please confirm this or let me know if I should get in touch with Colin to get answers. I am hoping that the posts I make while maintaining my car will serve as a reference to others. Also hoping that my lack of knowledge will cause many of the issues to be covered in the forums. Raj on the opposite end of the scale you are serving as the source of knowledge!

He has not produced any but said that one order would be enough to get them in production.

RajDatta

Bruce, I hope he delivers as promised. Last time he promised was last summer and I myself was on that list. Since then I have taken myself off the list. I couldn't wait any longer.
I would ask those questions cause they would clear things for me as well. My whole point is that if you go to a single piece unit, you will inherit vibrations similar to Fidanza unit unless you can figure out a way to absorb some of the impact that DMF normally will. Not sure what motorsports flywheel will buy you besides bragging rights and double the cost of a fidanza.
I think its a great subject that will benefit everyone.
Raj

josephsc

Guys, this is indeed becoming an interesting discussion and it's making me doubt about exactly how my car was set up. I had my clutch and flywheel replaced as part of a "fresh start" program during the first months of ownership. This was all done by a mechanic (who specialized in 928s, actually) so I don't have first hand knowledge -- except what's on the receipt, which says Fidanza and Sachs clutch.

I'm wondering about a couple of things...
* Spring-centered Sachs clutch is pretty standard for use on the 944 -- My 944 definitely has the spring-centered clutch (as I did this myself). Is it different for the 968? Did I just assume it was spring-centered?
* Why in the world did Porsche go to a DMF? Things were perfectly fine for the S2.

BruceWard

Joe, the clutch plate is not spring centered. You can see pictures of the parts of my clutch at http://968.2ward.com/index.php?ALBUM=ServiceAndRepair.

Both the 964 and 968 had the DMF. I think it may have been a new feature that they decided not to continue.

RajDatta

Bruce, a lot of new cars have DMFs. This all started back in the early 90s. BMW, Porsche and few other only have DMfs on their cars now. Supposedly, it quietens things up and absorbs driveline losses at the cost of DMF failres and expensive replacements .

josephsc

Thanks Bruce -- that explains alot. I was wondering why I wasn't having problems with my 944S2clutch/flywheel/968engine setup. Great photos -- much better than going out into the cold to take a look at my clutch!