8 replies to this topic

[FTodaro]

Last year at the beginning of the season I had the ACT 4 puck clutch disk and pressure plate installed in my car. I am now in the process of swapping the motor and when I pulled the clutch out I was surprised to see that it looks to me as if the friction material is just about gone. I did not install it so I do not know what I started with but now I think I have less than a 32nd of an inch of material left before I get into the rivet. I did not have a tool to measure it but I would say its about a 32nd of an inch.

So my first question does anyone know what they start out at? I am surprised its only going to last one season. Granted I did about 19 weekends 7 weekends were races the rest were DE's and or just track time were I did not run it that hard.

Also, How can I tell if I should replace the pilot and through-out bearing if they only have one long season on them. Frank.

[Black Sweeper]

I did the same thing , as a was prepareing for a motor swap I ordered a new Act 4 puck disc. The one in the car was about a year old with over ten race weekends on. Most weekends included a Friday practice day. Once I got access to the clutch I measured the thickness of the new disk pucks against the old one with a caliber and there was almost no differance. That same disc is still in there and working well with a total over 20 race weekends on it. It will be good to hear how long the Act last for other drivers.

As far as the bearing they are cheap and easy to replace so while you are in there I would just replace them.

[FTodaro]

So when you looked at the disk what would you say was the thickness to the rivet. I looked on line at some Hi res photos from Act on there products it from the picture it looks like they only provide about 1/16 of an inch of disk material so that might argue I am half way. Not being here before would like to know what others experiences are I guess I would rather error on the side of caution but if this is just mid way through the disk I don't just want to pitch it

[Keith Novak]

I asked the same thing beginning of last season. Mine was a hair over .3 in. Info I got from people who race a lot is that theirs had only changed a few thousandths in 5 years. Measure it again next year, then put it back in and figure you'll replace it one day, but probably not next year either.

[Dennis]

I put in a new ACT clutch for the 2009 25 Hours of Thunderhill. After that race and 7 more race days in 2010 I blew the motor. I got a new ACT clutch for the replacement motor and compared the thickness with a micrometer. The old clutch was only 0.01 inches thinner! I put in the new one since I had it there, but plan to use the old one in my next motor.

Dennis

[FTodaro]

Wow I guess it pays to ask a few questions.Not knowing what I started with I was convinced I was ready to replace the disk. So If I do not need to replace the disk can I assume that the Pilot Bering and through-out should be good for one more year?

[seege]

I think it's common for people to put the disk on the "while we're in there we may as well replace this"
list, especially if you come from bigger HP cars that use up clutches much quicker.I did it myself last year on my 1.6 and now I've got a like new 4 puck unsprung added to the spares pile. Anyone wants it cheap... pm me

[James York]

Wow I guess it pays to ask a few questions.Not knowing what I started with I was convinced I was ready to replace the disk. So If I do not need to replace the disk can I assume that the Pilot Bering and through-out should be good for one more year?

Those can go anytime. While you have the transmission out, install new.

I have never lost a clutch due to losing friction material. I have lost one due to a failed bearing.

[Bruce Wilson]

I think I've had my ACT 4 puck for 6 years now. I'll have to do the math on hours. I suppose they do wear out but I've never heard anyone actually say they had one start to slip. Definitely replace the pilot and bearing though.

-bw

Update: looks like about 225 sessions (~90 hours) on that disk. I may just have to leave it in for one more year