12-19-2006, 01:47 PM
[quote name='flash' post='29173' date='Dec 19 2006, 07:19 AM']wow - interesting that both spec and fidanza say that it wasn't safe, which is why they didn't and wouldn't do it
now if only we could find a disk
i actually had some spring center clutches here to try to make that work - unfortunately, i could not find one that would work with both our pressure plate and input shaft - either the throwout bearing got in the way, or the shoulder on the clutch disk was too short
i would have to step outside porsche for a disk, and just gave up at that point[/quote]
Bob, the thickest part of the Fidanza flywheel is the area around the hub where the bolt holes are. It had to be made this thick to maintain the spacing as dictated by the DMF, which is easily twice as thick as any conventional flywheel. Strength is not an issue; the positioning has to be maintained, so the flywheel is very thick at the hub to position the assembly in the stock location for the flywheel sensor, t/o fork, and central tube drive.
Take a look at my previous post with the backside pic of the Fidanza if you don't remember exactly what it looks like and how thick it is. My guy said the bolts were the weak point because of their length. He said that the hub could take a pretty deep cut, much more than the slightly less than 1/4” required.
For a disc, any 951 disc will work and I was going to use a turbo cup clutch or a 911 turbo sport disc that I’ve used before in high HP 944 turbo’s.
I really should buy another flywheel, have the machine work completed and prototype this for the group. I’m certain it will work and be the best of both worlds.
Incidentally, Porsche Motorsports used to sell a complete 968 sport clutch package for around $2200 back in the day. It used a steel one piece flywheel with a solid hub 996 turbo disc, but I think would accommodate a spring center clutch disc. I didn’t own my car when it was available or I would have bought it. .
now if only we could find a disk
i actually had some spring center clutches here to try to make that work - unfortunately, i could not find one that would work with both our pressure plate and input shaft - either the throwout bearing got in the way, or the shoulder on the clutch disk was too short
i would have to step outside porsche for a disk, and just gave up at that point[/quote]
Bob, the thickest part of the Fidanza flywheel is the area around the hub where the bolt holes are. It had to be made this thick to maintain the spacing as dictated by the DMF, which is easily twice as thick as any conventional flywheel. Strength is not an issue; the positioning has to be maintained, so the flywheel is very thick at the hub to position the assembly in the stock location for the flywheel sensor, t/o fork, and central tube drive.
Take a look at my previous post with the backside pic of the Fidanza if you don't remember exactly what it looks like and how thick it is. My guy said the bolts were the weak point because of their length. He said that the hub could take a pretty deep cut, much more than the slightly less than 1/4” required.
For a disc, any 951 disc will work and I was going to use a turbo cup clutch or a 911 turbo sport disc that I’ve used before in high HP 944 turbo’s.
I really should buy another flywheel, have the machine work completed and prototype this for the group. I’m certain it will work and be the best of both worlds.
Incidentally, Porsche Motorsports used to sell a complete 968 sport clutch package for around $2200 back in the day. It used a steel one piece flywheel with a solid hub 996 turbo disc, but I think would accommodate a spring center clutch disc. I didn’t own my car when it was available or I would have bought it. .
(This post was last modified: 12-19-2006, 02:14 PM by orphanowner.)

