Jeff B. in Michigan

Last year I installed an ACT 6puck race disk and the heavy duty pressure plate in my 98 SC 4Runner. I understood that this kind of disk (6puck) is not normally used in street applications but after burning up a CENTERFORCE duel friction set up in short order I figured the full race disk was worth a try.

I have mastered the unique launch technique required to avoid mega chatter but the clutch makes a very loud noise during engagement just before it locks up (so as I am slipping it the noise happens). The sound is best described as being very similar to the tire squeal that occurs during a slow burn out.

I wonder if anyone else has experienced this problem… I suspect it is caused by something resonating during the transition.

Thanks,

Jeff B. http://n8rws.com

SLC Punk

I take it is a ceramic clutch?

Does it have a sort of metal on metal sound?

If so then it is normal (so I have heard anyways)

X-AWDriver

Hmmm,isn't a 6 puck a bit overkill? I ran an ACT 2600 with the street disc in my 350hp Eclipse and it held up fine for about 2-3 race seasons. If I had a 6 puck my tranny would have never held up.

Jeff B. in Michigan

Yes it is copper ceramic material... and if I launch it very easy, it makes a metal on metal squeaking sound. If I have to get aggressive with the slip it turns into a very loud howling sound

My99

I'd say that's normal. I ran a 2600 in my DSM too, street disk, and never had any problems. I'd say you went a little overboard. I've heard that the chatter is something that you must deal with, as it is a RACE CLUTCH. Shouldn't hurt anything I wouldn't think... except your tranny.

Jeff B. in Michigan

Before selecting the six puck I investigated many clutch options. I discussed with the tech support folks at ACT, CENTERFORCE, RAM and F2UNING. Based on my discussions I formed a conclusion that packaging constraints in the 4runner limit the manufacture ability to make a pressure plate sufficient to hold the HP. I am not totally convinced that the heavy duty ACT pressure plate and street disk would not hold, but after wasting a CENTERFORCE duel friction system in one 1/4 mile pass I did not want to take the chance.

I can deal with the chatter but the noise is starting to bug me. As far as the transmission holding up, you have a very good point… so far I have had no problems on the street but I plan to give it a work out at the dragstrip in April (I won't launch it like a rocket though).

Thanks for your comment…

Jeff B

Jeff B. in Michigan

I checked ACT site, can't find a "2600" is that the Xtream pressure plate?

My99

Traction's your best friend and worst enemy at the same time. There's a line (or is it a pop) that separates the two. I don't nkow how much power you're putting down, but if you get some slicks or DR's, you better launch easy. Good luck!

X-AWDriver

I ran two 2600s (yes,it is the Xtreme but I think it now can be had in 2900 and + versions) in my Eclipse and got over 200 strip launches with them each which was about 3 full race seasons so I had good luck with mine.
Centerforce Dual Friction was a poor performer in DSMs also and was widely not advised to use with the AWD setup and high horsepower and frequent launches.

Jeff B. in Michigan

Thanks for the reply, when I bought my 6puck ACT did not offer the Xtream pressure plates (to fit a 4Runner). I just want to get it into the 14's using the 6puck then, I may have to switch the the street disk with HD plate (unless they start making the Xtream PP)

Thanks again...jb

Macgyver

I have the same setup as you in my SC'ed '98 4Runner and I got the squeeking when the clutch was new but now that I have broken it in the squeeking has reduced quite a bit. I'm very happy with how the clutch performs and it is very drivable on the street but I think I'm going to stick my stock disk back in because the chatter is starting to annoy my after having it for a year.

X-AWDriver

The 6 puck probably isn't so bad once you get used to it during normal shifting but it's the low speed manuvering that get's kinda old not to mention stop and go traffic.

Jeff B. in Michigan

Did you do the three hard slips to break it in? I did it that way and soon after the loud howling sound kicked in. I take it you don't experience the howling sound?

Thanks,

JB

Jeff B. in Michigan

I posted a sound bite on my page, you can hear it (crank the volume cause the gain is low) by following the link below:

Clutch noise wav

Macgyver

X-AWDriver I agree it's the stop and go traffic that gets old really quick, once I get going shifting is great. Jeff B. I may get that howling sound every once in a while but not all the time. I broke in my clutch by going very easy on it at first then after a while I drove it like I stole it...now it's fairly quiet. Did you machine the flywheel when you replaced the clutch if so what is your step height? Have you been in the rain lately? I noticed after I drove the 4Runner though some water it howled for a little bit.

Jeff B. in Michigan

Thanks for the reply(s). I did have the flywheel machined and it is a proper step per the shop, I can't remember the value though. I do notice that the howl noise is more noticeable if it is humid or raining. Also, it does not do it when the engine (flywheel pp etc) is cold.... once things warm up it goes to town...

Based on the fact you don't hear it all the time (I really have to work at the launch to avoid the noise at every single time) I believe it must be caused by something resonating under there… I have already tried using that sound deadening packing (same stuff I used to dampen the boom boom of my stereo in the body panels) in strategic places underneath but I have not found the magic spot yet… It seems that all magic spots are not so easy to find you know...

Duffdog

ahhahahahahaha!!!

I had one of those piles of crap installed in my s/c tacoma---too bad there was no way to stop the squeeling no matter what i did. I changed everything 3 times and tried breaking it in ---pull the ebrake and slip the clutch while flooring it for about a minute. I found out that the ACT ceramic clutches get really hot and burned 3 holes in my flywheel. I then decided to screw all the bs aftermarket crap and get another factory clutch. that actually worked the better than all the stupid, half-engineered aftermarket junk for "racing". and the cool thing is, i got better 1/4 mile times than all other s/c tacomas with my stock clutch--even head to head, they all had the problem of not being able to control the launch. Im sticking with the stock clutch from now on.

T

Jeff B. in Michigan

T... what is your best 1/4 mile et & MPH ?

Duffdog

13.9 @ 100 --- only with slicks