My Supercharged 01 Vette Clutch failure!
Updated: 6 days ago
About 3 years ago I replaced my OEM clutch with a Mantic ER2 single disk set up. The clutch is supposed to be rated for 600lb/ft of torque according to the vendor I purchased it from. The clutch was broken in and driven for at least 300 miles before any race or track use was undertaken. This clutch had about 4 runs on the naturally aspirated set up at ~400rwhp. After the super charger, I put another 6-700 miles on it of street use. The SC set up is ~650rwhp.
On my second run at Island Dragway - the clutch disk literally flew apart. My fist run was a shakedown run, I launched VERY easy and short shifted each gear to watch the Air/Fuel and listen for any issues. This run was an 11.80 at 129mph, 128.9 to be exact, but with a 2.3 60' time. Turns out the air dam in the front of the car is so low after the supercharger install - I was staging with it rather than the tires. I am VERY happy with the trap speed, I added almost 12mph on the first run, I'm sure there is a few mph in there with a good run.
Second run, I launched a bit harder and ran 1st and second out, I got a 1.7 60' time, which isn't bad for a 6 speed car. I was faster in each successive metric, 60', 330', and 660' than the first run - but at about the 330' the clutch gave way. I was on the way to a 10.6 run if you look at the 60' time improvement only, and this was only the second run on the new set up, AFR was showing 10.4 as well, which is pretty rich.
The time for this run was 12.5 at 91mph - lol!! I was pretty much coasting after the 1/8 mile.
Timeslips: Im "01" (left lane) obviously.
Here is where I'm at now, and few pics of the clutch, I think I spun the tires at about the 330 because the car was floating around a bit, and it bounced off the rev limiter a few times which caused the clutch to let go, but that's just a guess.
Here are a few pics of the clutch, the friction plate is really bad - I definitely over powered it or it wasn't holding properly.
I'm chatting with the Mantic USA rep now, and trying to get a good deal on a 9000 series twin disk set up from them, otherwise I am going to go with a Monster LT1-S twin disk. I'm of the opinion this clutch shouldn't have let go the way it did.
The Mantic 9000 is a $2000 clutch and a little out of my price range right now, but hopefully Mantic comes through for me.
The Monster twin, which is based off the GM OEM LS7 clutch, is $1000, still hurts, but not as bad as the Mantic - I didn't need this right now, LOL - but if you want to race, this is the cost!
The Monster has excellent reviews and is widely used in the LSx community. It's a dual disk clutch, which is nice.
I'm currently cleaning all the parts up and getting everything prepped for the install. More updates as they come! Hopefully the next update is the install itself.
Well, the Mantic Rep and the shop that originally did the Mantic clutch for me really let me down, they didn't want anything to do with it. What I think happened is the ARP bolts installed with the clutch were hitting the pressure plate springs and causing an issue, which is a shame because the ARP bolts are not needed, the Mantic kit comes with new GM bolts, the shop that put it in added them as an additional source of income, and really screwed me in the process. More proof you cant trust anyone but yourself to do something right.
Geoff, the Mantic rep wont return any emails - so I went with the Monster clutch.
I installed it and the clutch is VERY smooth. It's lighter than the Mantic and the pedal is as smooth as silk, I've only got about 40 miles on it so far but I'm VERY happy. The Monster kit comes with GM bolts as well - and yes, I used them.
I didn't take any pics during the install process, as I did a little each evening over the course of a week or so, and when I put the trans/rear/torque tube in I had a friend helping me so I didn't want to stop and take pics every few minutes.
This is what the monster twin disk looks like, you should mark all the parts for position when you disassemble it for install, as it's a balanced unit.
So far so good, going to put ~500 miles on it to break it in nicely - that should only take me 2 years or so - LOL!!
The end.......................................................................... for now............