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M6...yet another clutch. Let's play around a bit!

24K views 193 replies 42 participants last post by  STAGEUP 
#1 · (Edited)
First, the car: 2009 Pontiac G8 GXP 6M. I/H/E, GM Hot Cam, blah blah blah...MGW Short Shifter...443whp, 12.5 1/4mile on street tires (20") with a 1.9 60'

Driver: Plus sized, lead foot, likes to burnout, drift, rev to 6700 in every gear, even when nobody is around...and also sits in bumper to bumper traffic for 1-1.5 hours a day. The GM Hotcam with a lightened flywheel is the wrong setup for a car that sees a lot of traffic.

Point being: I drive a lot, and I am rough as hell. I also never cleaned the clutch fluid (I know better now)

Problems: Clutch wont engage in first/reverse with car running. commonly associated with Hydraulic issues. Also, clutch pedal engagement is very high, meaning worn clutch.

Previous set-ups:
McLeod Twin disk, and McLeod Adjustable slave
Mantic 9000 Twin disk, stock hydraulics (39.4lbs total assembly)

Each clutch lasted 10-13k miles.

Realization: 4,000lb car, 443whp, and aggressive driving means worn clutches. If you don't like this fact, buy an GT (or SS). If you treat the car nice, you will not have an issue.

New Setup:
Monster Flywheel with OEM C7 LT1 clutch/PP (about $1100)
GXP Clutch Slave... (I had originally ordered a ZR1 Slave, but Steve at Monster said that it was designed to only be used with the GXP slave)
Ideal Garage Master Cylinder: ($245)
Monster SpeedBleed remote bleed line ($50)
Tick Performance Camaro Stainless braided and wrapped Hydraulic line: ($130)

Parts have been ordered, and I'm also swapping Cams to a more friendly (at least in the low RPM) cam. Chris Henry will be doing the install, and expect to have her up and running in the next few weeks. I also plan on flushing the Clutch fluid at every oil change at a minimum (3k miles).

I know BracketRacer just installed the same clutch, but with all the expensive adjustable parts, and the fact that his car is hibernating for the winter, this will provide us some results a little bit sooner. Of course, I'll tell you that the clutch will feel great, works like a charm, etc...but let's see if the clutch lasts all of 2014...that will be the true test.

I'll add some pictures as we go.

Charles
 
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#97 ·
I figured that I would pop in here to mention that I have now run the Monster LT1S setup for an entire year quite successfully. I haven't made nearly as many runs as last year (75 in 2013, and 14 in 2014), but the clutch and setup that I run has held up to everything I have thrown at it. My car has a race weight of 4150-4200 lbs, and I am launching it at 4500-5000 rpm on 295 wide Drag Radials. I have a Katech C6 Heavy Duty Master & Slave Cylinder that have been modified to work in the G8 GXP. I am glad that I bought this setup, and other than the heavy clutch pedal that does have a negative impact on street driving, I love it!
 
#99 ·
the clicking noise you hear / feel could be busted pressure plate fingers.
the limp pedal is due to either the master or the slave going out.

i went through a slew of clutch / master issues on my gto and finally went
with a tick master and the monster lt1s twin disc. one of THEE best
combos you can get.
 
#100 ·
ehh that's my gut feeling which sucks bc this setup prob has less than 10k street miles on it! Just trying to decide between keeping the katech flywheel and going with the LS9X clutch/pressure plate or just dropping katech altogether and going Monster...
 
#101 ·
the monster twin disc is an AWESOME unit. holds 700 wheel
and has a factory feel. mine doesnt, simply due to the tick
master that i'm running, but a few folks i know in the gto
community that run the stock slave says its all factory feel.

good luck.
 
#102 ·
I figured I would pop in again, and after a year and a half, my Monster LT1S clutch set-up is doing great. It made it thru an entire racing season last year, and a road race and two drag races so far this year. My clutch fluid has no contamination, and the clutch pedal has never stuck. It was a great purchase for me, and it is still getting used pretty hard!
 
#103 ·
Thanks for the input guys! Monster def seems like the way to go, so I'll just have to get it apart and see how deep in my wallet I need to go lol.

The more I think about it the more it seems like the slave/throw out bearing that has gone out, possibly similar to what was noted here:

http://www.g8board.com/forums/showthread.php?t=197745&highlight=camaro+plastic+slave

If that's all it is, I'm wondering what my options are to replace/upgrade the slave and continue to run out the clutch...

On another note, while I've got the trans out would it be worthwhile to upgrade the shifter as well? I've always thought the factory shifter was adequate but while I'm in there I'd like to knock out as many things as possible
 
#104 ·
if your going to swap out the shifter, the easiest time to do it would
be with the trans out, no doubt.

there isnt really an aftermarket slave avail. there are a few custom
ones, but they either need to be measured for shims, or are too
thick for the application.
 
#105 ·
FYI, see the thread below where I updated with pics of my LS9/ZR1 slave after the throw out bearing came apart:

http://www.g8board.com/forums/showthread.php?t=197745&page=2

With all the other stories of these slaves failing, I'm inclined to go back with the OEM GXP slave. However, I'm wondering if the slave/bearing got overextended from my ported master cylinder, and if a shim would've helped the longevity? Otherwise I really don't feeling like taking the chance and will prob end up going back with a more proven setup (Monster LT1S?) with the GXP slave, albeit at a higher cost than rebuilding the Katech LS9R/X with the ZR1 slave....

Thoughts??
 
#107 ·
Yup just pulled the trigger from Maryland Speed and got a 5% discount plus free shipping on the LT1-S and billet support. I declined the slave from Monster bc I've seen OEM GXP slaves out there for less than $300, and I've already got a Tick speed bleeder and the porter master cyl, so I expect this setup to be the ****!!
 
#109 ·
hey don't MAKE me do some burnouts! haha
 
#110 ·
So just wanted to update the group with my new clutch...

As stated previously, I went with the Monster LT1-S with the billet release bearing support and OEM slave cylinder. I also went ahead and replaced the rear main crankshaft oil seal/cover/gasket which appeared to be seeping a bit. Gotta say that the intall was a piece of cake, and I just disconnected the shifter from the bottom without having to do anything from the interior of the car.

As soon as we got it back together, I could tell an immediate difference just putting it into gear. With the previous ZR1 slave and Katech clutch, it was always difficult to get into 1st or reverse from a dead stop (likely due to lack of a shim behind the slave), and was notchy at best. Now this thing drops into 1st and reverse like butter! I did a quick test drive as is, and noticed instantly why Monster recommends removing the clutch pedal return spring. The spring coupled with the additional hydraulic pressure wants to throw the pedal upwards right in the transition sweet spot where the clutch engages. Luckily its less than a 5 min job to pop that spring out, and other than a slightly heavier/stiffer pedal than previous with the ZR1 slave/Katech combo, I'm really getting used to it and it feels like what a stock performance car should feel like. I do have the Ideal Garage ported clutch master cylinder, so I'm not sure how that affects the pedal feel over stock with this setup, but the clutch takeup is more linear for sure. I'm almost through the 500 mile break in period, and there's no offensive noise. I still haven't heard this rollover noise that I was warned about, other than at low RPM's in 4 gear there is a more pronounced driveline groaning than before, likely due to the undampened pressure plate and the 1:1 gear ratio that does nothing to filter out those vibrations. Yet its only momentary, and just gives me a reason not to lug it around in 4th.

I've done some spirited launches and shifting, but nothing too hard until I click off some more miles. The only concern I have thus far is some intermittent coarseness in the pedal travel on occasion. On quick 1-2 and 2-3 shifts I'll hear a little slight crunchiness when pressing the pedal, and sometimes when coming out of gear I'll feel a little click or detent when releasing the pedal. The pressure plate has several kinds of progressive springs on it, so I wonder if they are just binding up and releasing, or if it's the combination of my ported master cylinder, or something else. As long as everything continues to function properly and the coarseness doesn't get worse, I'm inclined to think its just the nature of this system and I'm not too worried about it. I just cant wait to get some more street miles on it so I can take it back to the track!
 
#112 ·
Does the pedal feel I described sound normal, or anything to be concerned about??
 
#114 ·
My gxp has the dreaded sticky pedal. I plan to upgrade the clutch this winter and do a remote bleeder and replace the slave while I'm at it.

It seems like the monster clutch it the way to go. Does it come with new pilot bearing, pressure plate, and alignment tool?

Also, is leaving the stock master fine or are people replacing or modding it? I've heard of someone porting it, is that true? Anyway, I just want my clutch to work as it's supposed to. I basically only road race my car and need performance. Thanks!
 
#115 ·
So after the tremendous amount of research I put into buying a new clutch, I did find out one legitimate cause for the clutch pedal sticking issue. That is the fact that most pressure plates (including the OEM ones in our cars, and the Katech I was running) have a belleville washer type spring mechanism to disengage the clutch. At high rpms, the additional centrifugal force from the spinning inertia will allow the convex belleville feature on the pressure plate to remain compressed concave, thus there is nothing to push back on the slave cylinder/release bearing, and your pedal stays on the floor. When your rpms drop and you pull the pedal back up and pump it, you can then get the pressure plate to return to its normal state. All that being said, the Monster LT1-S (Corvette C7) pressure plate has a totally different design, utilizing a bunch of progressive springs and tabs instead of one large convex belleville type feature. So the Monster is certainly a good choice, and after a couple thousand miles on my setup (including mountain runs, an autocross, and a dozen passes down the 1/8), I have had ZERO sticking pedals.

I also do have the ported clutch master cylinder that I installed previously, only because the previous owner of the car had purchased it to alleviate the crunchiness going into 1st and reverse, but that issue was likely the result of needing to shim the ZR1 slave that was matched with the Katech kit. Shifting into 1st and reverse is like butter now with the Monster kit.

The Monster kit does not come with the pilot bearing, which isn't necessary unless yours is bad. Otherwise it comes with everything you need except for an OEM GXP slave, which I found cheaper (~ $276 http://gmpartsheadquarters.com/2009...ission_components-f_s_cylinder_92227219-item/) on one of the GM wholesale websites (there's several out there, so just google and try to find the one closest to you with the cheapest shipping cost). I also splurged for the $75 release bearing support from Monster since those seemed to have failed in other cars, and after spending $1500 on the Monster setup + slave, I didn't want to have to do this over again because I didn't go ahead and spend the extra $75... After I took apart my Katech setup, which failed because the release bearing came apart (i.e. overextended bc lack of shim), the plastic OEM release bearing support actually looked to be in good shape, fwiw.

All in all, the Monster is a good setup and drives better every day. The "click or detent" I mentioned in my earlier post is gone now, as well as some of the initial crunchiness. I think this was just due to the hard bite the new clutch disks had upon engagement, where it has since softened up a bit after break in. In fact when it was new, starting off on a hill was tough to do without breaking the tires loose bc the engagement was like an on-off switch. Now it's fairly progressive and linear, and I have full confidence banging through the gears. Hopefully that addresses any concerns you have, but if you have the money I'd say go for it!!
 
#116 ·
Awesome information jk! Thanks a bunch for taking the time to fill me in. Without the internet and these forums, can you imagine each of us having to do trial and error ourselves?

Anyway, to summarize, what I should need then is just the monster clutch kit, replacement oem slave, remote bleeder (where do I find this?), and the monster bearing support thingy. Are you guys running regular brake fluid or upgrading to motul etc?

Thanks again! This hopefully will save me tons of work and headache!
 
#117 ·
My pleasure JT! If anybody else can use this otherwise useless information, then it helps me feel better about spending the time to learn it myself lol.

But yes get everything you said. The previous owner of my car already had the speed bleeder installed with the Katech setup, but it is a must. I know Tick performance sells them for $49 (http://www.tickperformance.com/tick...14-camaro-ss-2009-pontiac-g8-gxp-04-07-cts-v/), but you can check around for who has best price bc Black Friday is the **** for car parts around here!! Honestly due to how frequent I (had been) flushing the clutch fluid, I've just been using some synthentic DOT 3 I had leftover from another job. You can mix DOT3 and DOT4, but not DOT5. As long as the temp range is acceptable for what you're doing, I don't think it's a big deal.
 
#119 ·
Monster clutch has been great to me!
 
#122 ·
#124 ·
Yea the LT1-S is what I have, and the same as the C7 Vette. It should be the best option for street with occasional track use, unless you're running a huge blower north of 700 hp.
 
#126 ·
Joining the Monster clutch club

After babying my stock clutch for the last two years, I decided it was finally time to upgrade and install a Monster LT1S twin disk clutch. From what I am reading, the 28lb flywheel is the way to go for our 4000lb beasts. My car only has 13,000 miles, so I see no need to replace the slave cylinder....wise decision? I'll pick up a remote speed bleeder, billet release bearing support and a throw out bearing. Am I forgetting anything? I plan on ordering everything on Monday. I spent part of my Thanksgiving holiday removing the transmission, clutch and flywheel so that I could inspect everything before making my purchase.
I'm looking forward to taking it to the track next year to see what it will do in the 1/4 mile!
 
#127 ·
Awesome. Thanks for the info. Does a new slave come with a throw out bearing or does the monster kit come with one? I'll definitely be replacing it, but it would be good to know if it comes with or if I need one. I'll also replace the pilot bearing while I'm at it. Does that come with the monster kit? Thanks!
 
#128 ·
The throw out bearing and slave cylinder are all one unit, and YES I would replace it unless you don't mind taking the transmission out to do the job over again when it fails. The pilot bearing should be OK, and the Monster clutch kit only comes with the flywheel (heavier one is better for our cars) and clutch disk/pressure plate
 
#129 ·
Excellent thread...

I'm hoping jkduty and STAGEUP are still sub'd here

My car has the McLeod twin disk w/aluminum flywheel (unsure of weight ATM) and I am having some issues. Occasional hard to engage 1st from a stop with occasional grinding into 1st or 2nd, notchy shifting and it is slipping when in high gear and throttle is applied (if engine speed is too slow for wheel speed). For example 30-40mph in 4th gear leaves you around 1.5k-2k RPM. If you floor it, the clutch slips.

This is the Livernois car with approx. 460wtq, I am unsure of the exact mileage of when all of the parts were installed but there is at least 10k miles on this setup. I am going to email them to see if I can get the specifics as to what the exact parts were used. The car has about 31k miles now.

I have changed the transmission fluid. I have bled the clutch system twice, once when I first got the car (I have only put about 500 miles on the car since I got it almost 2 months ago) and again last week. Each time there was a noticeable improvement in shift feel but the fluid gets contaminated again very quickly and starts to have shifting issues again. Could the slave seal be allowing the fluid to get excessively contaminated from the slipping clutch, meaning I have multiple problems? Is the clutch slipping because of a poor installation or failed parts?

I am wondering if I should just scrap everything and go with the same setup as jkduty, save for the ported master cylinder, which is backordered right now from IG anyway. Is it worth the wait?

I would get the Monster LT1S, buy a new slave from GM (is it the same as the one Monster sells?), Monster 28lb flywheel, billet bearing support, and the bolt kit and pilot bearing if they are not included. I would also hold out for the ported master if you guys think it's worth the time/money. Any input is much appreciated, thanks.
 
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