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Discussion Starter · #1 ·
Ok, This is getting old. I'm about to pull my tranny out for the 4th time in 6 months and I'm tired of it.


My first clutch I had in the car was with my basically stock set up that was around 300rwhp - 320rwhp. It was a clutch net 3 puck, ceramic, sprung clutch, stock pressure plate, and 11lb flywheel. This lasted me about 25k miles and I probably got close to 35 passes at the track on this clutch. Towards the end the clutch would start to slip. No big deal since I had a good amount of miles and abuse on the clutch.

btw, My car has a 1j in it.

Late last year I went single with it and put in the same clutch set up with a 20% stronger pressure plate rated to hold over 500rwtq. After the break in, I put DR's on my car it started to slip immediately. And only got worse. My only dyno was 380rwhp and 345tq on 15psi. Angry, I pull the clutch out to try something different thinking it was due to a shitty product. Which could have been the case since the ceramic pads were flaking off when you touched them. Oh and it cracked my 11lb flywheel :(

Early March 06 I received my South Bend Feramic, 6 puck, sprung with their recommended pressure plate which I think was 20% over stock. This clutch was rated to 500rwtq. I also put in a stock weight flywheel resurfaced with a twenty thousandth step. Right after the break in the clutch started to slip. Well this is a Feramic disc and they take much longer to seat themselves completely. I was VERY patient and gave this clutch close to 5000 miles before calling it quits. This clutch seemed to slip worse than the 3 puck and would do it on the street with shitty tires. My power may have been slightly higher since I’m running more boost but no where near 500rwtq.

I have a new slave cylinder, new master cylinder, no leaks in the system, I have adjusted the master cylinder nut to be sure the clutch was disengaging properly. Is there something I’m missing or am I getting shitty pressure plates?

Today I should be receiving my ACT 6 puck ceramic, unsprung, with ACT’s Heavy Duty pressure plate rated up to 518tq. I’ll then pull off the flywheel to have it resurfaced again with a twenty thousandth step.

My question is……..Why am I having so many problems with clutch’s slipping? Is there something I have missed?
 

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What is your break in process for a clutch? What exactly do you do or not do when you break them in?

FYI, getting the ACT UNsprung clutch is going to destroy that tranny. Very few people have had good luck with them and most end up frying the R154 long before the clutch wears out.
 

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Discussion Starter · #4 ·
Thank you. unsprung will not be going in the car then! I wanted to use a street disc but was unable to get my hand on one from the vender I used.


Break in is 500 miles no boost or very little at times. Basically just around town not beating the shit out of the car. Just to give the disc the proper time to seat with the flywheel.
 

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No One Ever Listens To Me
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yeah i was gonna say the same thing about the unsprung disk...not a good idea....

i think its a mix of improper driving (ahem) heh.....improper break-in (ahem) and crappy clutch choice.

;)
 

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Discussion Starter · #6 ·
IdealSupra said:
i think its a mix of improper driving (ahem) heh.....improper break-in (ahem)
;)
well wtf am I doing wrong? Seriously? I technically SHOULD be able to beat the shit out of it from day one and it'll seat itself and I'll just get alot of chatter.


Oh and should there be any issues with using a street disc?
 

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boost freak
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no, you shouldn't be able to just rag on the disc right off the bat. the whole system needs to "bed-in".....

based on your pix, that's a lot of heat into both the disc and the PP. i'd replace both master and slave and bleed well....ensure freeplay is correct and don't ride the clutch...
 

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Flying Dutchman Pilot!
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Its an ongoing problem. There is no good (reasonably priced) clutch for our cars out there if you drag race(which I know you do). The only one that'll hold a real 60' is the RPS DD, and that clutch knocks itself out of balance as soon as you 60' it. Once I started getting 1.5 60's my supra started spitting out driveline components. The whole being fast in the 1/4 with a manual car thing is murder on the driveline. It can be done but it is a lot tougher to extract ETs and you'll break a lot more parts. My best suggestion, GM auto if you are serious about dragging. It's much easier on the driveline and more consistent/faster.
 

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And just to add to what's already been said, there just isn't much along the lines or a really stand out good drag racing clutch for the MK3.

I realize that RPS is a bad word around here, but I had great luck with mine and so did many that I sold them to. If you are that serious about drag racing, I'd go with a more recognized clutch name and really do some serious research about it too. Not to say that you haven't done that, but you aren't having the greatest luck so far.

As DrJ said, there certainly appears to be A LOT of heat there. I'd check, recheck, and then check your master and slave again. Make sure its all bled properly and perhaps break the clutch in a little longer this time.

Break in procedure that I always followed: NO boosting, never above 3k -3500rpm if possible, don't ride the clutch when you take off from a stop, shift very slowly and methodically, and don't EVER let the tranny slow the car down. Take it out of gear when you slow down. I followed that procedure for breaking in a clutch and never had an issue. EVER.
 

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Discussion Starter · #10 ·
Trent I'll give your break in procedure a try this next time.

I enjoy going to the track but its not something that I'm 100% serious about. So getting a GM tranny isn't something that I have planned in the near future. Besides I have fun driving around town with a 5 speed. I think an auto would take away some of the driving fun. If I have to change a clutch once a year....NO big deal. But I need something that'll hold for some amount of time. I expect the clutch to hold while launching it and expect other drive train components to start breaking. That's fine but I need a clutch that will do it's job properly.

With my second 3 puck set up I would take the car to the track and the clutch would start to slip right away. I would lay out of it and then it would just start to slip again. This is why there was so much heat. I was pissed the clutch wasn't holding and knew it had to be changed so basically at that point I didn't care. (I should have to avoid cracking my flywheel) - - - NOT once have I done that with this Feramic Disc. I have been nothing but nice to this clutch. Anytime it would start to slip I would lay off the throttle 100% immediately.

I'll go pick up another new master and slave cylinder. I might as well cover all bases again to rule anything out that could be the problem.

I decided to go with the ACT unsprung because their sprung ones do not seem to be easily obtained yet and I didn't think a street disc will handle me launching it at 6k on DR's.

Thanks for the suggestions and advise. :)
 

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Not so boring anymore
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that sucks kelly.. hopfully you'll get everything worked out soon.. maybe time for a twin disc.. thats where im looking.. something that can hold the power and take the heat from launching..

remember the torque is rated at the flywheel, even with 400wftlbs (more boost) your prolly at like 480 at the crank..
 

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Flying Dutchman Pilot!
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Can always get the tilton setup. I got quoted for 4500 bucks for one. Last clutch you'll ever need though.
 

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boost freak
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psifactor said:
...I decided to go with the ACT unsprung because their sprung ones do not seem to be easily obtained yet and I didn't think a street disc will handle me launching it at 6k on DR's
i hope you change your mind....an unsprung disc spells certain death for the R154....
 

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Discussion Starter · #14 ·
It'll either be sprung street disc or sprung 6 puck. Even right now I'm suprised at how well my tranny still shifts with 160k and lots of abuse. Gotta love Toyota :)
 

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Moderator, l337 M0d3r4t0r
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i've had good luck with my RPS DD 3200LBS pressure plate as well. I had the 6 puck sprung hub. However I went though 3 trans with that setup. I now changed it up abit to make it slip a little more and so far so good. I put in the RPS again but this time with a full face kevlar disc... Engagement is noticeably smoother, however the kevlar does not like heat. After a few heated launches it will start to slip a little untill it cools down. Long as it's not heated it holds real good. Made 524 WHP last night on this clutch.

The probelm with the RPS 6 puck disc was it engaged so violently, and just shocked the trans every time you change gears.
 

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HMOOB VWJ NYOB MINNESOTA
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I dont know about you guys but my RPS 3200lb have served me well. 2 years back to back winner of tx2k5 and tx2k6. Drive everyday and drag/freeway race when ever I got a chance to. I got stock drive shaft, stock rubber mount, stock fly wheel, and 6 puck sprung disc. I believe that with all of these in place to absorb the abuse the life of all the parts will last a little longer.

The only down side to the rps 3200lb that I experience with is crack walk and very stiff pedal. The crank walk is no longer and issue and the stiff pedal feels ok once you get use to it.

So if you like you can try this clutch. :bigthumb:
 

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Flying Dutchman Pilot!
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I wouldn't waste my money. RPS even knows they have a problem, they added those welded nuts and bolts into their diaphragms to stop it from shifting. The way I see it, if I can't run an aluminum DS and semi solid motor mounts, this isn't the kind of clutch I want in my car. I'm a fan of the stock Flywheel, steel flywheels in general. I have numerous photos of mine and other members clutches with diaphragms that have shifted. It seems some have worked, some haven't, or maybe some have shifted but retained their balance to a point where it was unnoticable.
 

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when your machining your pressure plate, are you doing both the outer part, and the innear part?
cause i was told our flywheel is a 2 step flywheel
 

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psifactor said:
I decided to go with the ACT unsprung because their sprung ones do not seem to be easily obtained yet and I didn't think a street disc will handle me launching it at 6k on DR's.

Thanks for the suggestions and advise. :)
I blew up a ~40k mile old babied R154 with the ACT unsprung 6-puck launching a 3300lb hardtop on 225's that was making maybe 280whp on the stock CT. That wasn't dumping it either, that was slipping it from about 4500.

6-puck unsprung = dead R154. The Doc isn't saying that to hear himself talk.
 

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LEADED FUEL ONLY
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spoolint78 said:
when your machining your pressure plate, are you doing both the outer part, and the innear part?
cause i was told our flywheel is a 2 step flywheel
Pressure plates do not get machined. They are bought finished and ready to mount.

The stepped ring of the flywheel is the mounting point for the plate. That step is .020, IIRC. Search my name and flywheel and you'll find the correct number.
 
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