Why is my Clutch Trying To Explode?

[GenViper]

Hey, so I undertook a slave cylinder/clutch replacement this last week, and once it was all back together it's trying to explode.

I took everything down to the pilot bearing apart, and installed a new: Pilot Bearing, (Resurfaced) Flywheel, CCI Stage 2 Clutch Disc and Pressure Plate. It took me a while to get the transmission lined up (several days). Once the car was sewn back together, I started it up and gave it a test 'go' in the driveway to ensure proper operation and shim size.

I revved it, and it shook a bit past 2000 RPM. I tried to engage the clutch, and it began to engage about 50% of the way up. About 75% of the way up, the car started shaking like it was going to destroy itself or blow something out the bottom. I never put it all the way to 100%.

So I'm terrified that I have messed something up royally. The obvious problems with such shaking is a) effed up the pilot bearing (shaking in 'gear'), or b) flywheel bad (shaking in neutral).

After total disassembly, the flywheel seems fine, except for a tiny 'chunk' missing, which may have been before the refinishing, not sure. The pilot bearing seems fine. The clutch and clutch mating surfaces (pressure plate surface, flywheel surface) all share a small (1/4") contact patch around the area which doesn't exist across the rest of the surface. I know it won't be perfectly even as it wears in, but this thing seems like I'm going to explode my car!

So can anyone tell me what's wrong, or at least where to look? I've included photos of the Tranny spline for 'grease level' reference. Too little? Could too little grease be causing problem with the Pilot Bearing/Etc? Could my Pressure plate have been on unevenly? How important is it that all of the Plate's spring 'teeth' are even? Is that one small piece missing from the Flywheel a big deal? Should I be worried about the small (1/4") contact patch across the assembly? The non-flat part is facing towards the transmission, right? Might something else be wrong?

[1BADAIR]

could be a few issues but 1- the flywheel isnt clocked right. that extra hole lines up with another hole.

the pedal distance is from the flywheel being cut and clutch toleraces. you gonna have to measure and shim the slave

[GenViper]

...I did not realize that about the flywheel. So if the extra hole isn't lined up with the other hole, it could be off balance/cause these vibrations? What are the holes for?

The clutch came with a pretty hefty shim which is on it, and seemed to have the pedal action engaging in the right place.

[1BADAIR]

im not sure what the extra holes are. i have changed a couple dozen and always lined them back up. most performance clutches with chatter until broken in.(some never stop). if the engagement fells right then leave it in. after break in , push the clutch a little while slowly accelerating to verify there is some free travel at the top of the pedal and that the slave isnt holding the clutch open

[GenViper]

Alright, well I'll follow your sage advice and try and line it back the way it was before (here's hoping it left marks).

Also, something that I see mentioned several places is proper 'Indexing' of the flywheel and pressure plate. What exactly does this mean/how do I do it? Might that be causing the vibration?

[GenViper]

Nm, I have uncovered the meaning of 'indexing' the flywheel. I was trying to 'index' the wrong part and google was confused!

Is it necessary to have the flywheel/clutch disc/pressure plate setup balanced at a shop, or is that overkill?

[bri2203]

I strongly suggest ballancing the flywheel and pressure plate.

[birdie2000]

I strongly suggest ballancing the flywheel and pressure plate.

x2. I had this done with my CCI clutch and the machinist told me it was out quite a bit.

Are LS engines internal balance or external balance in the rear? I know on LT1s there is often a dowel pin in that hole location so the flywheel is indexed to the crankshaft properly because they are externally balanced in the rear and there is a weight on the flywheel that needs to be in the right position.

[GenViper]

What kind of shop will do this kind of balancing? I called my local Automotive Machine Shop who I've used in the past and they didn't, recommended I try a local (quite well regarded) transmission shop. Called them, and the guy had never heard of anyone balancing the Flywheel/PP combo, but suggested i try some place that's about 45min away. I live in Dallas, TX which is not exactly a small place, so somewhere around must do it, since people in another thread have recommended this as well...

Also, how much should I expect to pay?

[1BADAIR]

places that build torque convertors can.
most machine shops should be able to