3.2 V 2.7 Fly wheel

[MFozz]

How did you initially determine that it wasn't balanced?

Originally Posted by Gelbster

To understand the differences ,you'd have to dissect some DMFs ?
Jake would have an interest in the answer your question?And he probably has lots of old DMFs -take-offs in his dumpster.
But here is a simpler idea. My brand new LUK dmf was not perfectly balanced! I had it balanced. O.K. only a few grams of metal removed from the periphery but not good !
I'll follow this with interest. Good Luck.

[Gelbster]

Checking and adjusting balance on a DMF is a job for a skilled specialist -certainly not me !
John Edwards of Costa Mesa R&D did mine.
"The final issue is that if the clutch/DMF assembly wears and runs out of balance it can cause severe engine damage by overloading the crankshaft main bearings. This problem is especially prevalent on the 986, 987, 996 & 997 2.5, 2.7, 3.2, 3.4, 3.6 & 3.8 models, For these reasons Ninemeister highly recommend replacing the Porsche DMF at the same time as a clutch replacement and will only warranty a clutch package when fitted with a new DMF."
The whole story is here:
http://www.schaeffler.com/remotemedien/media/_shared_media/08_media_library/01_publications/schaeffler_2/symposia_1/downloads_11/4_dmfw_1.pdf
&
http://www.schaeffler.com/remotemedien/media/_shared_media/08_media_library/01_publications/automotiveaftermarket/poster_1/downloads_29/luk_dmf_poster_de_aus.pdf

I hope this helps

[jsceash]

Well for the curious. I had the 2.7 5 spd flywheel and 3.2 6 spd Flywheel on the floor side by side. All the external measurements where the same. Mounted they set the same distance from the motors machined surface to the face of the flywheel. The Pressure plate aligns on the pins on the flywheel as do all the mounting bolts. I don't know how to measure the resistance in the dampening springs but the 3.2 springs are stiffer, there is more resistance.

[Meir]

Originally Posted by jsceash

Well for the curious. I had the 2.7 5 spd flywheel and 3.2 6 spd Flywheel on the floor side by side. All the external measurements where the same. Mounted they set the same distance from the motors machined surface to the face of the flywheel. The Pressure plate aligns on the pins on the flywheel as do all the mounting bolts. I don't know how to measure the resistance in the dampening springs but the 3.2 springs are stiffer, there is more resistance.

Just to make sure I follow.
The two FW that you are competing are both new?

[jsceash]

Originally Posted by Meir

Just to make sure I follow.
The two FW that you are competing are both new?

To answer your question No. I have a brand new LUK 98611401201 (2.7L 5-SPD) OE Flywheel. I'm comparing that to a Lightly Used LUK 98611401206 (3.2 L 6-SPD) purchased from a dismantler. Less than 10K. The surface is just lightly polished enough that you can tell where the clutch disc road, the machine groves are still fully visible.

I've asked before what alternatives I had for my Base car with a 3.6 motor without going to a LWFW to have better C, PP, FW longevity. It looked like I could use a 98611401206 (3.2 L 6-SPD) DMFW, on the 5-SPD as a more suitable option base on the horsepower I output. I believe this is my next step base on the comparison. I have no doubt that it will fit at this point. No, I don't intend to put the used one in my car. Obviously it was more cost effective to buy a used one for a comparison, this way if it didn't fit I'm not discarding a new flywheel or giving it a way for 1/3 what I paid.

[BYprodriver]

Originally Posted by MFozz

How did you initially determine that it wasn't balanced?

No drill marks from being dynamically balanced.

[Gelbster]

Correct -the machinist drilled out several shallow bores in the outer circumference - where it was heavy .
It was balanced with the pressure plate attached and marked accordingly.