968 Engine Rebuild - light-weight flywheel?
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Thanks for all of the feedback guys!
With respect to my configuration (and I apologize to the original poster for the semi-threadjack) I agree that keeping within one brand is generally for the best, but if all the critical dimensions of the two parts are identical there shouldn't be any difference. Shouldn't being the key word there! ;-) All that said, I will likely be going with the Spec setup - lightened flywheel, sprung hub 6 puck disk and lightened 3400# pressure plate. I do plan to have the entire rotating assembly balanced once I get the flywheel and clutch assembly in my hands. Also an aside - checked on the clutch fork - a new one lists over $400, which I should have seen coming knowing the cost of the similar 944 unit. Does anyone know the guidelines used to determine if a used clutch fork is within tolerance? Thanks!
With respect to my configuration (and I apologize to the original poster for the semi-threadjack) I agree that keeping within one brand is generally for the best, but if all the critical dimensions of the two parts are identical there shouldn't be any difference. Shouldn't being the key word there! ;-) All that said, I will likely be going with the Spec setup - lightened flywheel, sprung hub 6 puck disk and lightened 3400# pressure plate. I do plan to have the entire rotating assembly balanced once I get the flywheel and clutch assembly in my hands. Also an aside - checked on the clutch fork - a new one lists over $400, which I should have seen coming knowing the cost of the similar 944 unit. Does anyone know the guidelines used to determine if a used clutch fork is within tolerance? Thanks!
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300....talk to these guys. I know of a couple of people who gotten ltwt clutch/FW set ups here. http://www.area951.com/index.html. The name of the guy escapes me but he's well know in the 951 community. He cutom machines everything and has done several 3.0T build outs. You can pm Tom M'Quinn for a reference. This is who built/is building his 3.0T.
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I have LWFW on my 968, and I am quite satisfied, but there's some driveline rattle on 1800-2300rpm, espec. when lifting the throttle. Have you guys tried to apply S2 harmonic balancer on 968? I guess it's heavier, and would thus reduce the vibrations? any thoughts for this?
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I have the S2 harmonic balancer and a dynamically and statically balanced engine, and in my opinion the rattle at 1800-2200 is significant. Enough for a passenger to look at you funny and enough that if a friend drives the car they think something is wrong.
I have a friend with the same setup minus the S2 pulley and the vibration/sound is the same.
The engine revs much more freely and I really like the LW flywheel/solid disk for all types of driving... except for the rattle.
I'd like to try and eliminate it. I may try another harmonic balancer on the transmission side of the torque tube (custom of course). Another interesting thing is that the 928 torque tube had a balancer - does anyone have any details on this?
I have a friend with the same setup minus the S2 pulley and the vibration/sound is the same.
The engine revs much more freely and I really like the LW flywheel/solid disk for all types of driving... except for the rattle.
I'd like to try and eliminate it. I may try another harmonic balancer on the transmission side of the torque tube (custom of course). Another interesting thing is that the 928 torque tube had a balancer - does anyone have any details on this?
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So then what's the deal? How is it that a 2.5 has no vibrations, a stroked 2.8 has no vibrations, a bored 2.7 has no vibrations, but with the 3.0 there's no way to have a SMFW without vibrations? The 2.7 had a single mass, and everyone with a 2.8 also uses the single mass. I've never heard of anyone with a 3.0L 8v complain about it (until now) so I figured it was because either the spring centered 951 clutch stopped the noises, or the 951 tranny is not subject to making noises.
I'm wondering about the S2 setup. It has a (sort of) SMFW, a heavy PP, extra weight in front, and the whole deal still weighs less than a 968 setup, but it doesn't rattle. Is it just because of the slotted driveshaft? Or the 5-speed?
I'm rebuilding a 951 TT right now and will be putting it in this weekend! I don't want driveline rattles!!!
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Wow...looks like I got lucky by a stroke of luck witht eh 5 speed I have now.
I was really kinda worried about this issue by upgrading the perfomrance by going the 3.0L turbo...looks like I may not have to worry so hard now.
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By the way - this is/was a great discussion.