555ss

I did a search for C5Z clutch for road racing and got nothing so I thought I would ask what are the faster guys using for a clutch in C5Z no motor mods.
The issue is the "weights" or “dampeners “ on the diaphragm spring that are like 5/8's by 1.5 inch long are breaking off the stock GM clutch this has happened to 2 cars in 2 weeks both car have been driven hard for 2 years but taking out bellhousings is getting old. I am looking for a stock type feel with higher RPM longevity. Both clutches came out looking pretty new with almost no wear.
Thanks For any help
Bob

JeremyGSU

I'm running a Monster Stage 2 right now. So far so good.

JRMaroon1

I'm pleased so far with the Mantic ER2 after two and half years and about a dozen weekends. This is on a car with 475 WHP.

FASTFATBOY

Had a Monster 2 in my LS6 equipped 3800lb Z28, ran it for 5 years with no issues.

Monster 1 should be fine also.

I put a stock LS6 clutch back in my car.

Last C5

I've been running a 7.6 Fidanza dual disc with the Fidanza aluminum flywheel. I first put in my Lingenfelter LS6 for two years, then in my built LS2 for two hours, and now it's been running in my new LS7 that puts 580 to the wheels. No problems at all.

flash911

How about this:

https://www.corvetteforum.com/forums...e-trailer.html

SouthernSon

QM now has the 2 disc clutch pac that is much more friendly for DD duties as well as track. Danny P. can hook you up with one. I did have the QM 3 disc optima V. It was, indeed, an on off switch with the very aggressive camshaft I am running. With a more mild cam the 3 disc might not be as difficult. I hate to rev engine and ride clutch, thus the reason for going to the new 2 disc set.

CHJ In Virginia

I'm going to be in the minority here and vote stock C5-Z06 clutch. My factory clutch went 47K miles with almost 20K of those being track miles. Still going strong when I sold the car. If you modify and increase HP that is another story.
If you are breaking arms off, it sounds like a bad install or driver abuse.

555ss

Yes Both cars get beaten HARD they are basically race cars and we run to win.... Both failures were traced to HIGH rpm stress neither car had more than 7 k miles on brand new GM clutches. Glad yours is working but Stock won't be going back in our cars.
Thanks to all who replyed your help is appreciated
Bob

C5Z06CE

I drive my c5Z hard at the track and originally replaced the stock with Mantic ER2 clutch. That clutch was ok at first but as I learned the car and drove it harder and harder it began to fail after only 8 or so track days. The main issue I had was poor shifts at high RPM. Particularly my issue was rough shifting 3-4 up shifts and the lack of ability to downshift 4-3rd when braking and heel toe downshifting after several hard laps. There were several times that my clutch would not allow me to shift 4-3 and I had to cut the sessions or entire track day short. I estimate that I lost nearly the cost of the clutch in track fees, hotel and travel fees on the number of times this happened. I switched to a Quarter Masteer 10.8 race clutch. It is surprisingly street friendly but more on/off than stock or the Mantic. It is the same clutch used in the Continental Tire Series Camaro Z28 and can be rebuilt without having to replace the entire clutch. THIS clutch works PERFECTLY. No issues. No I can run hard and never miss a shift.

QM clutch FTW!!!

555ss

THANK you I was thinking of using the ER2 but you are the second person that mentioned High rmp hot issues.... That is the issue down shift heel toe to 3 from 4 and putting the engine a bit too high and rmp mechanically the engine can take it but the stock clutch cannot....LOL

SouthernSon

Excellent point. Going deep and letting the engine decelerate to low rpm before downshifting sometimes gets really busy when searching for a little more rpm to exit. This can result in missed shifts. But, you don't want to downshift too early because of the high rpm issue. There are those turns that require compromise on more than just the line. Some clutches are definitely more intuitive, some take a more extended learning period. And just when you get comfortable with your clutch someone hands you a dog ring tranny.

redtopz

Stock clutch works great for racing if driven properly. But if you want an upgraded clutch this quartermaster is awesome. Drives like stock, but is lighter and holds more power. You can also order with the Tri-lite release bearing or use a stock bearing. The kit also includes a remote bleeder. Use SRF fluid and you won't have any issues. Don't downshift at high rpms to save your clutch and engine.

This QM clutch is used in world challenge cars with a twin disc option, but the single disc is more than enough for a stock LS6, LS3, or LS7.

http://www.quartermasterusa.com/qm/o...wheel-kithtml/

SouthernSon

Redtop, this is the one I am currently using: the two disc with rally material .250". This one is almost stock feel for engagement compared to the older 3 disc I had. I am using the tri-lite bearing. This one spins up quickly but is still easy to engage with my aggressive cam.

http://www.quartermasterusa.com/qm/c...2-corvettehtml

C5Z06CE

I too use the twin disc one. After several very hot track days at Sebring in 98 degrees there was not even a hiccup with this clutch.

redtopz

Yeah I have the same one in my race car and love it! But I would hate it on a street driven car. The one I linked drives like a stock clutch on the street, and would be a great upgrade from a stock clutch. Still has a lot more mass and inertia than the 7.25" button flywheel clutch that you and I have, but much less than stock. Kind of a nice compromise.

SouthernSon

Just to be sure we are talking the same clutch for those that have not run either and are searching for good information, the clutch comes with 3 discs or 2 discs. I ran the 3 disc and found the engagement to be very short and abrupt. However, I am now running the 2 disc ( .250" rally style) and find it to have a long engagement and very easy to modulate. Either disc setup can be used with the same package in my link above.

Oh, btw, I am running stock M/C but using the tri-lite bearing. With the three disc I was running a tick M/C.

JLZ06TR

Slight thread hijack but it may benefit the OP as well, What clutch master cylinder are you guys running with these?

OP I am basically at the same point you are in, but I have decided on the Monster Stage 2 with lightweight flywheel. My car is heads/cam. I dont think you need anything much better than this unless you are making or planning on making considerably more than 500rwhp.

Joshboody

I'm going to thread jack also... sorry.
I assume I will be in the market for a new clutch soonish (100k miles now)... there's a bunch of options.

LS1 basically stock but may bump to 430-ish rwhp if I do change the clutch. My car is HPDE and golf transport. I'd want something that wouldn't scare a non-track buyer (if I decide to sell), but also holds up well to HP bump and track... and not too pricey if possible. I was thinking LS7 unit with lightweight flywheel.

Thanks for any feedback!

SouthernSon

Josh/JLZ, with the older 3 disc QM I had to go to the Tick M/C (adjustable). With the current 2 disc .250 Rally QM I am back to OEM clutch M/C. The main reason for the clutch pacs is to reduce flywheel weight for a faster rev with the engine. If you have ridden bikes then you know the feeling of having no flywheel. Engine just spins up quickly and decelerates quickly with no heavy flywheel attached. Of course, this changes the rev matching/downshifting timing completely. The clutch pacs are great on the track but do take some getting use to for the street.