I just had a Tilton 8.5 cermetallic clutch put in my 05 sti.
whever I take off from 1st gear the car shakes violently and "clunks".
All other gears are fine even in hard shifting.
I noticed it also does this if you engine brake after hi boost.

Is this normal? Broken something? or improperly installed clutch?

thanks for the help. I dont post here often. But I did hear the HIIC hangs out here!!.

 

Sounds like you just installed yourself the "common" clutch shudder problem.

Has something to do with too light of a fly wheel, was common on the 02 WRX's I believe.

 

so no fix but a better flywheel? Its the tilton one..
Anyone else ?

 

Not sure what you can do to fix it if it is the clutch shudder.

Subaru's "Fix" was to put a heavier flywheel in if the car's were brought in under warranty with customer complaints.

 

Is this problem common on 04 WRX's?
Thanks.

 

not for the 04.

 

Thanks I was just wondering.

 

I don't have experience with cerametallic friction facing but the material determines how smooth the engagement will be from a dead stop. Not much slippage is needed during shifting once the vehicle is moving. Factory clutch discs use a material that allows for smooth engagement but the tradeoff is that under high engine torque loads, it may overheat or wear sooner if driven improperly or subjected to abuse like drag strip starts.

In one former car, I used a clutch with two clutch discs, which requires a special pressure plate. With two discs, there was almost twice the torque capacity, while still providing stock-like engagement with very light pedal pressure. The tradeoff was that for drag racing or any application that requires very fast shifting, the inertia from the extra weight of a dual-disc clutch makes the transmission synchros work a lot harder. In the old days of F1, it was a real trick to pull out of the pits because you either stalled the engine or did a burnout because the clutch was either engaged or disengaged. Everything is a compromise.

You'll probably have to find someone with a similar clutch setup to find out if they have engagement issues from a dead stop.

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0==WW==0
"…axles of evil…" - george w. bush

 

1) why did you put a race clutch in your car? Tilton is known for making NASCAR clutches not daily driving clutches....

2) could also be a faulty tranny mount. remove it. If you can flex it, its bad.

 

I don't think this is the infamous "clutch judder" at all. I think it is an extremely stiff clutch that isn't very streetable and that hasn't been broken in yet. A ceramic-disc clutch may take 300-500 miles of very careful driving to break in properly. If you're not putting down 300whp you might have gone a bit overboard in the clutch department; standard organic clutches can hold up to 350 crank HP on the Subaru tranny...