Clutch problem

[Sheltie2306]

Hi,

 

Recently, I have this problem with my 3 years old original factory clutch. After I did a few drag launches, when shifting from 3rd to 4th gear, somehow, there

[BMW320i]

Off topic: What car is it ? What ECU piggy/standalone your using for LC ?

Edited September 27, 2005 by BMW320i

[Sheltie2306]

bug eye sti, ecu is utec, it's a piggyback at less then 20% throttle and become standalone beyond 20% throttle. Support launch control and flat shift. But my clutch can't handle it to take full advantage of the feature.

[Sky8807]

check and adjust clutch free play. might help

[Sheltie2306]

Hi friend, unfortunately, not that simple. Anyway, we can't adjust the free play for this car, it's fixed.

[Felipe]

wat the hell is launch control? i tot i heard this term in F1. wat is the process of using it?

[Sky8807]

Maybe, the gears(3 and 4)had worn a little that cause this symptom, since the clutch freeplay cannot be adjusted. Or the gear oil might be due for change.

[Sheltie2306]

Just check out the gear box detail, it has only single cone synchromesh from 4th gear onwards, the rest are double or triple, probably that could be the reason that for whatever result from overheating, the single cone is not able to sync the rotation.

[Sheltie2306]

That's a special mechanism that allow you to hold the clutch in, slot in 1st gear, floor the throttle, and the ecu hold the engine at a pre-programmed rpm using ignition cut. The result is fire popping from exhaust, turbo boost built up, the whole engine is highly tensed with all the ponies eagerly waiting to rush off the starting line. When the light turn green, simply let go the clutch and the car will shoot off like a bullet. It

[Imuya]

"The result is fire popping from exhaust"

 

Are you serious? even if launch control is installed on a stock car?

i tot fire from exhaust is anti-lag system?

 

i reckon you're not in Singapore?

[Sheltie2306]

I am in Singapore, and of cos, I don't do such thing in Singapore. I will rather contribute RM to our friendly country TP then our local TP, They will thank me, and talk to me more polite than the bank teller. Unlike the local TP that will all out to show off their authority and their hungry of ego

 

Yes, you are right, the technical espect of lauch control is in fact similar to anti-lag, but just for different purpose. Anti-lag is slightly more complicated in fact, as it even need some kind of mechanism to maintain throttle opening even when the driver is not steping on the throttle. I don't have anti-lag, even though I have the launch control.

 

There's other method of launch control that don't have fire popping, which uses fuel cut method to control the rev. My ecu can support both, but I choose iginition cut because I like fire popping

Edited September 29, 2005 by Sheltie2306

[Elfenstar]

bug eye sti, ecu is utec, it's a piggyback at less then 20% throttle and become standalone beyond 20% throttle. Support launch control and flat shift. But my clutch can't handle it to take full advantage of the feature.

 

That answers one thing for me... (the car)

the stock WRX clutch cannot take launching all that well... 5 7000rpm launches and my friends clutch died on his 05 WRX (8500km mileage). The clutch plate was blue (from the heat) and the pad was worn to its rivets. Also the more highly powered the WRX, the more likely you will kill the gearbox if you get too strong of a clutch, so i say dun go crazy on the clutch unless you want to shot-peen or cryotreat the gearbox syncros first.

 

Whats happening to is normal, dun fret. If you need to change the clutch, i would say exedy heavy duty clutch plate mated to the organic clutch. No more than that as i would rather have not-so-good launches or a dead clutch than a dead gearbox. On the STI you could probably run the exedy heavy duty button clutch, but thinking abt sg road conditions, i wouldn't reccommend it.

 

Edit: I forgot to mention, if its your syncros that are starting to get worn, try using redline lightweight shockproof (blue- i think). The NS and SAU (nissan) boys, and toymods (toyota) boys have very good reviews on using redline when the syncros are starting to get worn. It may be a little notchy when cold, but they run perfect when the gearbox is heated up. If it was the clutch, go with redline superlighweight shockproof (yellow)or the manual transmission oil (mt80 i think) as it's generally better than most of the gearbox oils around and would extend the life of the gearbox without the cold notchiness of the lighweight. Its fine if you want to run lighweight shockproof on a well running gearbox too. Btw, while we're at it, try using the heavyweight shockproof (red- i think... if i made a mistake then swap the colours for the heaveyweight and lightweight) if you've switched to mechanical diffs.

Edited September 29, 2005 by Elfenstar

[Sheltie2306]

Thanks for the infor

[Elfenstar]

No probs. I don't really handle WRX's all that often. Just that this happenned to my friends wrx about a month back. Btw, i got most of the gearbox and clutch info from STI australia and prodrive aust.

 

Edit I forgot to mention, I'm using lightweight and heavyweight redline gearoils in my g-box and mech diff respectively. On a 180sx though.

Edited September 30, 2005 by Elfenstar

[BMW320i]

bug eye sti, ecu is utec, it's a piggyback at less then 20% throttle and become standalone beyond 20% throttle. Support launch control and flat shift. But my clutch can't handle it to take full advantage of the feature.

 

 

I know of people running on stock clutch launching at 6000rpm frequently using slippage method and there haven't been any problems (other than accelerated wear and tear). These were done on WRXs.

[Elfenstar]

I know of people running on stock clutch launching at 6000rpm frequently using slippage method and there haven't been any problems (other than accelerated wear and tear). These were done on WRXs.

 

My friend just dumps the clutch at 7000rpm. No slippage method used :p

[BMW320i]

Your friend worships me for a living.

 

But seriously, sooner or later the gearbox is gonna ORD. (If stock)

[Elfenstar]

Yeah it's a when, not an if in his case... i'm guessing you launch the same . Nah this guy has cash and doesn't know what he wants. He's been saying he wants a straight cut os giken gearset, i'm sure he'll be able to change everything when he kills the standard box.