allngn_c5

So do you guys that have an exedy twin plate ever go to the track? If so how many passes have you made? The reason I ask is because I put about 28000 miles on my Exedy twin, but as soon as I went to the track with the 541 rwhp 505 rwtq 402 and 20 passes later she was slipping, and slipping badly. With that being said she did hold enough to drive from Detroit to Atlanta.

I currently have an RPS street twin lite. No complaints at all, drives like stock too. Talk about best of both worlds. Going to add a Tick Adjustable Master Cylinder in the spring. No other reason then had one instance of the car not wanting to shift and I don't ever want to experience it again. (Tried to grab 4th and it wouldn't come out of 3rd, @ 6700 rpms) Can you say I kissed the rev limiter ?

tez_14_2000

What kind of money was the RPS clutch if i can ask? and how long have you run that set up?.. have you tracked that clutch yet?
what about twin plate noise.... ?

LF97C5Vette

So this weekend, myself and two of my friends installed my Centerforce Dual Friction 12" clutch, new slave, and a new pilot bearing. We sucked out all the crappy fluid, and loaded her up with fresh Motul 600. I have a ~500 mile break in period which I'll do my best to abide by... but no promises... and I'll post my results as soon as I make a few, conclusive redline shifts w/o the pedal sticking to the floor. I'm so anxious I hardly know how to contain myself... hehe

On the clutch, I have to say so far I'm satisfied. It doesn't rattle or anything (I was worried about the weights) and went in w/o any hic-ups. The install took myself, and a couple friends about 9 hours to do, using Dope's install guide. (Huge thanks again to Dope for writing it.)

The engagement, is a bit more aggressive, and by that I mean, it has a bit more bite than before. It also bites a bit earlier than the LS6 clutch I had. In addition, the pedal feel is a bit firmer. But only for the bottom half of the stroke. The top half of the pedal stroke feels like stock and the last bit gets a tad firmer, though not much. So all in all I have to say I'm very pleased with the Centerforce 12" dual friction clutch so far, as it has a very streetable feel - to me at least.

The F1 Racing light weight flywheel was 16lbs instead of the stock 24lbs and mate a noticeable difference. I took before/after video revving it and I'll try to get that uploaded and posted. But right off the bat I can tell it revs a tad quicker, and when I downshift it rev matches almost instantly. It also made almost no impact on my idle, which is good since I have a fairly aggressive cam.


I'll post as soon as I finish my 500 mile break in, and see if it resolved my clutch problem. Thanks for everone who posted in this thread, and I hope that anyone with clutch problems can get theirs solved as soon as possible.

LF97C5Vette

Well, break in finished - drove it around town excessively.

I can conclusively say that with a heads/cam package induced Sticky Pedal syndrome the sure fire solution has been a Clutch/Slave swap.

I went to a Centerforce 12" Dual Friction clutch and Factory GM Slave. Problem solved.

Bleeding clutch = No Fix.
Turkey Basting fluid = No Fix.
Flushing Fluid at Shop = No Fix.
Pulling Return Spring = No Fix.
Replacing Master and Slave = No Fix.
Replacing Slave, Clutch & Flywheel = Fixed!

If your clutch was fine - and after a heads/cam swap it went to hell, I'd clean up your fluid and if you still have the problem, go straight to a NON-GM Aftermarket Clutch. Skip all other steps.

Good luck to everyone, and thanks for the replies!

-Dan

Corvette Don

I am interested in those videos, I love my Centerforce 12", its a great clutch for the $$$

LF97C5Vette

Know any good software for cutting two videos side by side? lol

-Dan

Dope

Great work, glad to hear it worked out for ya. I know the pain of clutch problems myself, it's like driving a new car again!

Dope

SmoothFRC

When my car was stock - i had the problem and they replaced the Slave under warranty. I kept the stock clutch (car only had 20k miles on it). Problem went away.

I had the problem again at ~30k miles and they authorized another replacement of the slave. This time i changed the clutch and put in a Spec 3.

I never had an issue with high rpm shifting after this point. I changed the Clutch with ~65k after an incident with the Spec 3 and put in an RPS Single. I also changed the slave at this time, and still never had the problem again. I just recently pulled the RPS Single and put in a Monster 5. Changed the Slave again (just the thing to do these days)... Only 700 miles on the clutch, but so far no issues with high RPM shifting.

This time i did install a remote bleeder, as these do provide some value. I was having issues with the clutch disengaging with the RPS when i was at the track the last time, but this was not at HIGH RPM, but at idle after i glazed the clutch.

SmoothFRC

did you NOT install a remote bleeder when you changed the clutch?

LF97C5Vette

I installed the remote bleeder after I replaced the slave the first time a couple years ago. Some forum members had me convinced it was a hydraulic issue related to the slave... so when I pulled it apart, I just did the slave/master and remote bleeder and didn't put in a new clutch. Waste of time, and money, because it fixed nothing.

The remote bleeder is quite handy.

-Dan

Chevy Guy

I have a 2001 6 speed that takes DOT3 fluid, I take it everyone here is upgrading to a synthetic that meets/exceeds DOT 3 and 4 spec?

B Neat

I put a remote bleeder on mine, but I haven't used it in 57,500 miles! Even when I replaced the torque tube couplers I didn't bleed the slave, I just topped it off. One thing is for sure, I wouldn't install a clutch without one!

btw, Exedy twin, 57,500 miles, 550+ whp, 1.6 60's, and it still feels exactly the same as the day I put it in. I even "over slipped it" at the track so badly it started slipping at the top of 3rd and 4th, but that was 5,000 miles ago. I guess it glazed one of the plates or something, after a week of normal street driving it went away...lucky me!

SmoothFRC

Agreed the remote bleeder is handy.

What did we learn from this exercise? I realize that you went through quite a bit to resolve this issue for your car - and ultimatly it took replacing the clutch to see a resolution...

So...What do you think was wrong with the stock clutch? I dont have alot of technical knowledge of how the clutch system works - but my understanding is the pressure plate creates pressure against the friction disk and the flywheel. So when talking about high rpm shifting - wouldnt a weak pressure plate cause slip and be "easier" to disengage? The component to disengage the clutch is obviously the master/slave....

Just seems like a fairly simple process - but the slave always seems to be the root of issues around here

For other folks reading this - I think what many of us has found, was if you are going in there to replace the slave for this particular issue - it is worth the minimal investment to replace the clutch if the stock one is still installed. Just seems there may be something else in the mix here that has not yet been identified.

LF97C5Vette

The interesting point to me is - when the clutch pedal sticks on the floor, the clutch is ENGAGED, meaning the slave was not successful at disengaging the clutch when you depressed the pedal. So, to me, the problem clearly involves the hydraulics. (Especially since you have to pump everything back up to use the pedal again)

The kicker is - replacing the slave and master by themselves, doesn't fix anything.

That indicates to me that the GM clutch is somehow causing a problem with the GM slave at high Power/RPM scenarios. Maybe the GM Clutch has some issue that compromises the slave - and replacing the clutch by itself also wouldn't have fixed the problem. I'll never know since I replaced both this time...

There's definitely a hydraulic element to this (for those with stock cars especially) and determining what part the clutch plays in modified cars to cause this problem with clean fluid would be nice... but so far, I don't think anyone has been able to figure it out...

-Dan

2003Torch

Engine upgraded to 383 so slave replaced and installed a Textralia 0Z700 no problem after two years now suddenly just the other day the peddle goes to the floor and stays there during any mild acceleration over 4k...

My opinion is that something is going on with the clutch flywheel assembly causing excessive heat effecting the slave...

I will take a look this weekend with the boro...altough most likely either way the rear tranny is comming down!

jtkeller

I had a Centerforce DF (along with slave/throwout bearing) installed over a year ago at the same time as my C5R motor - car makes 540/530 to the wheels. I had the same problems everyone else has with my old H/C/I setup that made 490/420 to the wheels.

Never had much luck with Centerforces in the 5.0's back in the day and was skeptical about this one, but I flog the car every chance I get, bounce off the rev limited at 7k rpm on more than one occasion, hot lapped it at the Texas Mile over and over and it's solid.

What's the most power anyone here is running on there Centerforce?

Gray Ghost GS

Try Ulead Video Studio 11

Paul 75 L82

I've just read this entire thread. I'm getting ready for a clutch/trans replacement. This is great thread and everyone was really, really civil about all the different choices a person can make in clutch selection. I'm trying to make a final choice on clutches and this thread helped. Thanks to everyone.

Atok

I think good working hydraulics helps mask the root cause which in my opinion is the pressure plate. Fluid helped mine but I think it's a temporary help. A better designed pressure plate is the "correct" fix. Waiting for my clutch to throw in the towel then I'll replace it with something better.

WKMCD

Never stuck stock. Stuck once with the LS7 clutch (460RWHP). Never stuck with the RAM Dual Street with Cartek adjustable master. Has never stuck with the Spec 3+.

FWIW: I'm replacing my master cylinder with a tick. Into 4th quickly is iffy and getting it into reverse could be a little easier.

My fluid stays clean..with occassional flushing.