Why break-in a clutch?

Because it still looks like this after driving for 15 miles! The bright band about 1/2 inch from the inside edge of the resurfaced face is where the clutch was riding.

I probably averaged only 1 mile between cruising on 5th gear on this new spec stage3+ clutch. No clutch drops or hard shifts on those 15 miles. The pressure plate looks a little more evenly wearing than the flywheel.

did you have an issue with it. or just showing as a reference?

Just showing.. I've seen posts about people toasting clutchs immediately after installing by hitting the strip or doing burnouts or whatever else. Figured it was an opportunity since i had to pull the trans since I had to figure out the vibration and rear oil pan leak. The clutch was working great.. really grabby.. I kept stalling it trying to move it around the yard. Probably the new 3.35 1st has a fair amount to do with that.

awesome!
i welded my stage 3 to my flywheel last summer after doing a 1/8 mile burnout... i think that why it was so long once it locked it wouldnt slip! i had about 14k on my clutch then.

have you found your vibration?

15 miles isn't a whole lot to break in a clutch. In your pic, I can see the disc is kind of polishing the whole flywheel, but it is only wearing in on the inside edge, where you pointed it out. You should always break in a clutch for several hundred miles so the friction material can wear evenly with the flywheel/pressure plate. This will guarantee the clutch disc has the most surface area to grip the flywheel/pp. Sure it grips great now, but it should be a whole lot better when properly worn in. Of course ceramic discs or race oriented may not require this but if yours is an organic based material, a proper break in period will help.

lol BJL, 1/8 mile burnout.
Re: the vibration, I updated the thread. With what I've seen in the trans and what was suggested in the thread, I'm gonna replace some bearings.

15 miles isn't a whole lot to break in a clutch. In your pic, I can see the disc is kind of polishing the whole flywheel, but it is only wearing in on the inside edge, where you pointed it out. You should always break in a clutch for several hundred miles so the friction material can wear evenly with the flywheel/pressure plate. This will guarantee the clutch disc has the most surface area to grip the flywheel/pp. Sure it grips great now, but it should be a whole lot better when properly worn in. Of course ceramic discs or race oriented may not require this but if yours is an organic based material, a proper break in period will help.

Yea, that's why I posted the pic up.. "a picture is worth a thousand words." There's been no beating on the clutch yet, and won't be for a good number of miles for break-in.