bobushka king

All right to start off, my car is a MY 01 with about 23k miles on it. The clutch recall was done about 15k miles ago, so the clutch is still fresh. I don't beat on my car, this was only the second time drag racing, the first I actually attempted to launch.

the story:

A local drag strip was holding a "cruise night" last night, which offers a free pass down the drag strip. Since it is the last one of the season i decided "what the hell" and ran my car. So I get up to the line and rev it to about 4500 rpm to launch (I'm afraid to do a "real" launch), the light goes green, I let off the clutch about half way with my foot half way on the gas. I feel the clutch grab, then I engange the clutch fully and mash the gas. Everything is going fine until about 7000rpm, the rpms just shoot right up, so i shift to 2nd clutch isn't grabbing car just reved, try thrid and then fouth same out come as second gear. At this point I knew there was a problem so I put it in 5th held the clutch down and slowly eased the clutch on. It slipped a bit then finally grabbed. I rolled across the line with an impressive 21.8 e/t.

Now going back to my parking space It's shifting fine and everything seems to be in order (except my car reeks of burnt clutch). So I park it for about and hour to let it cool. On the ride home everything felt ok on up and downshifts, everything except when starting from a stop as I let off the clutch it chatters a little bit and sometimes slips just a bit (maybe for a quarter of a second) when just fully engaged (in first gear only). Besides that its fine. But after a 50 mile ride home the car still reeked of burnt clutch.

So my questions:
1. Has this happened to anyone else?
2. Will the chattering go away after time with just normal driving?
3. Is this something I need to replace the clutch about?
4. I sat in about 2 hours of stop and go traffic before I ran, did that have anything to do with it slipping like it did?
5. Will the smell go away after time or is the car going to stink everytime I drive it?

thanks in advance, I'm just a little shaken up because this is the first problem the car has ever given me.

AssassinJN

2 hours of stop and go traffic could definately heat up your clutch. The smell should go away after a day or two, however the problem you may have now is a glazed over clutch. All the stop and go drying heated up the friction material on your disc and your launch was just the final jab of the knife.

Couple questions:
1. how long after getting to the track was it before you raced? (need to determine how much cool-down your clutch got before you raced it)

2. how does your car drive now? Go for a quick drive if you havn't yet today and let us know if your clutch is working normal again or not. If it is then you should be fine. If it's still slipping just a little bit, then as I mentioned earlier you probably glazed your friction material and should probably have your clutch replaced if you tend to drive your car with any real vigor (which I assume you do since you own a s2k).

Best of luck.

KnowledgeIsPower

i have an 01 and am going to the track this sunday...not a good story to hear (although i will be doing a 6k drop). hope everything works out man.

what is the clutch recall on 01s? is there anyway to figure out if mine has been done or needs to be done? (not trying to jack the thread if anyone has a link or can send me a pm that would be great)

FormulaRedline

Oops, you blew it!

There are multiple threads in the Street Encounters section right now explaining how to launch you car properly, I'll try to summarize here though as I know not everyone visits that forum prior to attempting this, as you've had the unfortunate position of demonstrating to us.

First of, never, ever feather the clutch in this car while racing. This is the most important thing to take away from this post. Now I will explain why, and what to do instead.

Clutch assemblies tend to consist of a clutch disk made of friction material (think sandpaper) connected to the transmission that is pushed by springs against the flywheel on the engine. Ideally, this connection doesn't slip and the engine speed to transmission input ratio is 1:1. You can push against these springs by pushing your foot down on the clutch pedal, disengaging the clutch from the flywheel. If the clutch and flywheel are touching, but you've pushed in the clutch pedal slightly so there is less force pushing them together, the clutch is allowed to slip, letting the transmission input move at a reduced rate. This might be something you would do when starting from a stop light, as logically connecting the stopped wheels to the moving engine in a 1:1 ratio is impossible, something has to give.

While accelerating the car, all of the engine's energy cannot be immediately put to the ground. The drive train must first be brought up to speed, from the transmission to the wheels, and then finally the road. This extra energy during launch (and the beginning of subsequent gears after shifting) has to be dissipated somehow.

Slipping the clutch can dissipate this energy by converting it into heat. However, in our car, the revs are SO high, that the heat generated is enormous. The heat actually glazes over the clutch material. Now instead of sandpaper, you have glass. If you burned your clutch up early, then in the mid range when you let the clutch out, just the pressure form the springs might have let it hold. But then as soon as you got into the powerband at the higher rpm

bobushka king

Thanks for the input everyone.

Assassin: The car was sitting for about 40 minutes before I got on line to race. The line for racing was about 25 minutes stop and go.

Formula: Thanks for the detailed post, it's funny I thought by slipping the clutch at a lower rpm I was saving the car, now I realise I was hurting it. I just thought (again I'm not a drag racer/street racer so launching is new to me) that slipping it into gear at lower rpms wouldn't have the shock of being dumped in at a higher rpm. I guess i was wrong. I'm going to drive it for the rest of the season as is and see what it does. If it's still messed up I'll just replace the clutch and be done with it.

FormulaRedline

Yep, it's a common error because on most cars slipping the clutch works. But the high rpms kills ours. For example, if you look at something like a 600cc Honda CBR engine, which can rev up to 14k rpms, you'll find a wet clutch, one cooled by oil, to prevent this very problem.

So the way to save the car when launching is to use up a little tire, a small price to pay! As I said though, your clutch should be fine again once you drive a little more on it.

KnowledgeIsPower

good writeup redline

spectacle

...

Its fun to feel the back end go a little sideways when you drop it too

Heres a video of me doing this for the first time at the track...side stepping the clutch at 6k on street tires with decent tread...I'm the red s2k in the 2 middle races

http://video.google.com/videoplay?do...67586396119977