CDH76

Just curious, those that are running s/c + @ 650+ HP how is your stock clutch holding up? Assuming you've put some miles on your car, of course.

I see a lot of post of people with 650+ HP and no mention of swapping the clutch out so just curious is it holding up or needing replaced?

Theta

900whp on stock clutch and flywheel - not dead yet.

That being said, I've not done any hard launches - I start/roll out in 2nd and punch it. Blink once and the race is over.

DOUG @ ECS

All of our 650+ builds are on the stock clutch going fine. That said if you are a hard launching drag racer then don't expect long life to it. Heavy street use seems to be fine so far though.

Sgoochds650

My car is in the same category as Theta's . Roll racing it seems to do fine and I've probably raced it 10 to 15 good roll races so far. While doing the half mile event down in Ocala I did experience some pretty bad clutch slip once I got into 3rd. I was pretty hard on the clutch trying to get the car off the line without completely shredding the tires. By the time it Got into 3rd there was enough heat to cause it to slip . It would actually flash the tach. I thought I was spinning the first time and then realized what was happening and smelled clutch. Flashed the tach 3 times before holding enough to continue the pull. After the car cooled down the clutch seemed to be normal however I know if I heat it up in first or second it's definitely going to slip again in the high gears. I plan to change out clutch fluid before I run the car again.

CDH76

Good info, what I expected. Was just curious because I never seem to see clutches listed in the mod list.

Theta

I wish you could send me a bottle of the clutch smell.

I smell some pretty strong rubber in 3rd planting it hard on the same hill/dip of choice out here, but it still resembles rubber.

My BMW clutches have always smelled like burnt roadkill, and smoke usually comes from the underhood area. Never flashed the tach (except on wheel spin) on this C7, so I'm crossing my fingers.

I'm starting to think we should have done the torque tube and rear end, but at the time, there wasn't much out there (when we planned all of it in May/June).

PRE-Z06

Same clutch that's in the C7Z that makes 650hp stock, modded one has gone 9s and cut 1.4 60'...we have run the clutch with our flywheel in other LS applications and cut 1.4 60' as well hot lapping, holds up well and is the best stock clutch ever produced by GM.

Theta

Now that some good information to have! I had expected the clutch to be different, but I feel a lot better about it now.

I was kind of treating it like a timebomb before.

CDH76

That is comforting for sure. Thanks man

Sgoochds650

The link above is the pass where I experienced the clutch slippage. It's hard to hear much other than the GTR kicking my a$$ but if you listen closely you can hear the car rev 3 separate distinct times in when I shift to third. I feel like I did a decent burnout. Thought I got the tires turning quickly without building much heat in the clutch. I did slip it quite a bit off the line to avoid spinning anymore than necessary. I think I was slipping it a little in second also since the car will really blast the tires in second. When I went to third though it was just a clean shift with no intentional clutch slippage whatsoever. My buddy who is a very talented street car racer says it was purely my fault the way I was driving. I thought I was on my way to a decent pass but ..... Any advice or constructive critisim is welcomed.

Higgs Boson

no water burnout, lots of black dust, very little smoke. hard to say for sure but it looks like you did a bit of a clutch burnout.

Sgoochds650

[QUOTE=Higgs Boson;1589061869]no water burnout, lots of black dust, very little smoke. hard to say for sure but it looks like you did a bit of a clutch burnout.[/QUOTE


That was my second burnout ever in the car. I'm learning Higgs cut me some slack. LOL!

As soon as the tires broke loose I was completely off the clutch. It does look like some clutch dust though now that I'm looking closely. I wasn't sure how hard of a burnout to do on the R888's. Definitely a little water would have helped get them going a little easier. That was a tricky surface until 3rd gear.

Could you tell when I made it into 3rd and was having trouble with the clutch slipping? It really surprised me. I initially thought I was spinning but wasn't the case. I am planning on changing the fluid out and testing the clutch out close to home just to see if or how damaged the clutch is. It still feels good but I haven't heated up since then. Only couple 2nd and 3rd gear rolls. I hit a deer so my car is in the body shop so I haven't been able to test it so as soon as its done and the weather cooperates I intend to see where I'm at.

Higgs Boson

Haha, I didn't mean to bust your chops, I have definitely done a clutch burnout back in the day.... I suppose the increasing load of 3rd/4th gear was enough to get the clutch to slip after it got hot. It's hard to say without being there.

You need a lot of horsepower to do a dry burnout on sticky tires at the drag strip (different from the street). You don't want to do a burnout in the water, just get a little film on them to get the wheelspeed going.

Theta

Don't feel bad, Shawn. I'm embarrassed that to this day, I can't do a proper burnout. No way I'd try in this one on the street. I'd let Higgs show me, but I'd need new rear tires afterward.

Still need to figure out how to start one from the water pool properly without 'going swimming' like some of the clueless people I've seen at tracks do.

I hate (in jest, of course) how even the most massive GTRs just sit there patiently and wait for the other car to warm the tires. Damn their superb AWD launch control!

Sgoochds650

Lol. No problem. I'm learning for sure.

We will be in Houston for TX2K15 approx 3-18 (Wednesday through Sunday). Then in Dallas for a few days following. Will you be anywhere near during the event? I see your TX tag in your avatar.

Sgoochds650

Sean I tend to get stage fright when around all the people so I'm always afraid I'll embarrass myself. I do know it's best to back into the water if possible.

The funny thing about the GTRS at Ocala was once the power levels got on up there we were seeing a few of the guys doing burnouts which was pretty cool. They launched like a rocket also. The UGR Lambos never did burnouts or dry hops at all. They all launched very softly and built speed like crazy by mid track. GTR was beating the track with a hammer while the Lambos appeared to beat it with a feather. Top speed for Alpha Omega GTR was around 226 and a UGR Lambo went 233.

This link has a great video of Ron blasting the tires on the Z06. This is what it should have looked like when I did it!

Theta

A GTRS doing a full burnout is insane - must have been a sight. From the stories about the Lambos, they should have had chutes.

I was actually really lamenting not doing something to the clutch until PRE-Z06 chimed in on this. If there's somebody who would know how much of a beating these can potentially take before failure, that would be him.

I'm more afraid that the clutch would lead to a new diff, half shafts, etc... Once I start modding, I can't stop. The whole VR thing started with a cam - Ron can tell you how that ended.

Higgs Boson

I wish I could go! I live about 3-4 hrs from there so not too far, but work has me locked down pretty hard this time of year..... I can sneak out for a Friday test and tune but that's about it.

0SNL/MonsterClutchCo

You can ask the guys at Vengeance Racing about our clutch upgrade for your C7.

Motohead279

My car is torn down right now getting a motor upgrade. I have about 9k miles with it supercharged and they said my clutch looks in really good condition. I drive it hard on the street but I have not done any days at the track yet though.