Guys

My clutch started slipping the other day in 3rd,4th, and 5th gear under any amt of boost. I went ahead and ordered an ACT HD clutch kit and a prostreet flywheel, but heres something interesting....

I have never seen a bad clutch act the way mine does. Since the Evo is my daily driver i have been babying it till I put my clutch in, however last night, i was feeling dumb so I went out and did a few WOT pulls in 3rd/4th gear, and I found this. The clutch actually slips for like 1.5k rpms and then grabs again and holds till redline. I did this several times with the same results. I know typically glazed clutches can be worn back into working, but I've never seen this happen.

Anyone have any insight or shared the same problem?

 

You are probably feeling the effects of the restrictor in the hydraulics and a clutch that is on it's way out. People speak a lot about glazing, but they don't realize the truth about it. Actual glazing or lapping of the surfaces is normal and is encouraged to promote long clutch life. The clutch holds less power once broken in (or glazed) but the wear rate is very slow from that point on.

On the other hand, overheating the clutch by excessive slippage under power will burn the glaze off and melt the resins that hold the friction material together. At that point the resin becomes more like a lubricant than a binder and the clutch slips all the more. Once the clutch is allowed to cool again, it will actually hold more power than before until it is allowed to glaze again. Every time you burn the glaze off, you lose a bunch of clutch material of course and shorten the clutch life.

 

Well

I went out and launched the car a few times in a row, with about 20-30 seconds of cool-down time in between. That is when it first started slipping. I let it set over night, and from then on is when i've been having the problems

 

wow i have never heard it put the way actman put it but now i think of it, sure does make since, thanks for summing that up.

 

Here are a couple more thoughts:
By overheating the clutch, the flywheel warps and this causes more clutch problems.
By burning off friction material you affect the working range and before too long the clutch will slip because it is out of the proper working range. On the EVO there are stops built onto the pressure plate that bottom out when the disc is too thin. BTW, this is why clutch failure (slippage) happens so suddenly on the EVO. It seems like one day it works and the next, it slips like mad.

 

well, this is why i went with a different flywheel, i've heard the stock one has problems warping. I realize going with a lightened flywheel isnt the greatest idea to combat this issue, but my guess it still does better than the stocker

 

Pulled the clutch out and replaced it last week, the rivents werent coming out, but it looked worn, and definately had some hot spots on the flywheel and pressure plate. All is well with my new clutch/flywheel!

 

this is about the same thing that my clutch is doing.. now ... (putting down 306whp if it makes a differance) and clutch diesengages very high (like its sort of engaged just by my foot being on the pedal)
wat are my options? looking to buy something by this week ? thanks

 

I had to hurry my search as well, the best deal I found was prostreetonline.com

Alex sold me an ACT HDSS kit with the prostreet 10.5lb flywheel for one hell of a price. PM me if you're interested, i dont know if he wants to give that out here