Clutch inspection this morning

I think you found it, David. Those ridges look ominous.

Any idea what would cause that, Stan ? I've done only 30,000 miles on it, don't push it too hard, never drop the clutch or burn rubber. Just an odd combination causing this ?

I'll be into the clutch shop tomorrow and have them do a looksee. I'm taking the heads in tomorrow too and if they look ok, they'll get a complete redo and looks like it's straight to Montreal to pick up a JDM 2.5 litre engine and on to a mild Frankenmoter I go. For this I'll really have to get my shyt together for additional motor mounts / refresh the tranny mounts and figure out what to do for a clutch disc.

David, whatever you do, make sure you have the flywheel resurfaced before you put a new disk in it. If there are any hot spots on the flywheel, it will chatter again. I thought your flywheel looked normal for 30k miles though.

David,

No idea, other than my continuing opinion that the clutch set-up on a Type 1 is a weak link. as we've discussed before, I've had some clutch-chatter since the beginning. I've got a "copperhead", which is organic material on one side and copper pucks on the other. I believe my chatter is coming from the organic material as well.

Regarding mounts, etc: I have a tube-frame IM. I have no frame-horns, and the rear engine mounts hang from a cradle. This makes ALL of the standard braces, etc. something that is unusable for me.

The theory is always that the engine is moving around, creating chatter. To this end, I have fabricated two different rear cradles, which mounted the engine "911 style" from the Type 3 bosses on the pulley side of the motor, and which utilized 911 motor mounts. I built the mounts to clear my (various) exhausts, and they've not been particularly effective. I'm presently not using either one.

I've run a mid-mount using 911 hardware. I've run with a front transaxle mount and without. I've had no less than 4 different Bowden tubes on the car. Some of it was better than others, but none of it was the do-all and end-all. I've actually used the rear cradle to change the pinion angle (by pulling up on the engine), without any effect.

Right now I'm using Rhino mounts on the rear, and a red urethane mount on the front. I know it isn't ideal, but I have a late nose-cone, and my options are limited. I've tied the cradle back into the frame, which eliminated the possibility of a mid-mount (until I can figure something else out), and makes replacing anything in the rear-end of the car a pain in my own rear-end. It's still not right.

I'm pretty sure after 10 years of dorking around that all of this has nothing to do with the engine moving around, and has everything to do with the clutch disc. I was hoping your spring center/dual surface disc was the answer, but as I look at what you've got going on-- I think the issue is with the organic elements we are both running on once side or the other.

I really wonder if a full Kevlar disc wouldn't be better. I don't know. I'm anxiously awaiting your results. 

Thank you for that excellent report, Stan. It seems to be a tricky animal indeed.

One last thought before I get to the clutch shop tomorrow. If I have a 1600 lb (Or was it 1800 lbs ? Kennedy stage one pressure plate and it is exerting it's force on my segmented Kevlar side of things. Do you know why the Kevlar side should be segmented ?...what's the advantage ? In other words, those segments which are about 1/2 the surface area of a full disc are really taking the equivalent of double the 1600 or 1800 stage one pressure plate.

I'm guessing the answer might be that the segments are " up to the task at a correct rate of grip " and being segments, might dissipate heat better.

Another thing I thought about is the material in the pressure plate surface compared to the flywheel face surface. We'll ask about that too.

Any ideas appreciated....I'll be in the clutch shop tomorrow and will report what I find.