I've had my fair share of races in my time and ive won mosta em, and ive always raced them while double clutching. But lately ive heard crazy things like "Why would you double clutch?" and "Are you A FRIGGEN MORON? dont double clutch!" and other such comments.

So my question to you guys is this: should i double clutch when racing? and if not, why? I can understand that the rpm's instantly redline when the fly wheel engages which could cause stress but i always took that as ona the many risks of racing.

Who knows, maybe im the crazy one... so any comments you'd like to put about the subject would be good

LET THE DEBATING BEGIN!:bigthumb:

but what the hell is "double clutching"??? is that like dumping your clutch at high rpms? whatever it is, it probably depends on your clutch. stock clutch=owwie. after market=maybe.

doubleclutching is unneccesary. and just curious why are you doing it? did you hear it in a movie or something? all you need to do is shift quickly and accurately. and i'd have to second that "friggin moron"

Originally posted by PreludeMOFO
LET THE DEBATING BEGIN!:bigthumb:

There is no debate. Overall it's a waste of a good tranny and that's all.

Double clutching doesn't hurt anything if you do it right. If you are downshifting and cause the engine to overrev (as you describe by redlining the tach sometimes) than that is very very bad. The technique itself is not harmful, though its not really necessary anymore. Today's engines all have synchros which eliminate the need to double-clutch. unless you have a full on race car with straight cut gears it probably wont make you any faster.
I Heel-Toe, and rev match when upshifting and downshifting, and actually this is very good for the transmission and clutch. Keeps clutch wear to a minimum, and takes the stress off the tranny. I am trying to practice my double-clutch, but more because its just kind of exciting and fun than out of necessity. Makes a neater noise, and makes people wonder what the hell you're doing.

Also, to my knowledge, you only double-clutch when downshifting. This because you have to speed up the gears before engaging the next lower gear. I'm almost positive you never do it while upshifting. So by "racing" I take it you mean autox or something, not dragracing. Double-clutching while accelerating in a drag race is actually working against what your car wants to do.

Double clutching was originally used for semis and pre 1960's cars. dont really need it for todays kind of cars

well looks like my double clutching days are over, thanks for the help

Am I correct in thinking that double clutching is having the RPM's matching what the new gear will be pushing when the car goes in gear. If that is the case it would not make sense to do it during a race becuase it could mean you are waiting for the RPM's to drop before you take the next gear.

But I am not sure if I have the correct understanding of the term.

Sort of, that's really more just "rev-matching". Double clutching is used to match the gears in the transmission up. Without synchros, if you were tottling along in 3rd gear and wanted to go to 2nd, you would need to spin up the transmission because 2nd gear spins faster than 3rd gear at a given speed. So you would do this by clutching to disengage the engine, then shifting to neutral, then delutching and revving the engine to spin up the transmission to the right speed, then clutching to disengage the engine again, the shift into 2nd, then declutching and continue driving. Clutch in, shift to N, clutch out and rev, clutch in and shift to 2nd, clutch out. Thats double-clutch... Whew.

ah so now i have a word to go with that thing i do. someone told me in order to keep his turbo spooled, he does something similar while upshifting. you know, in order to bypass the lag. he called it "double tap". i told he was full of shyt cuz once your clutch re-engages, it's just gonna drop your rpms back down which'll slow your exhaust output, which'll slow your turbine. which will induce lag. n e 1 know about this? i'd like to for when i get my STi.

hmm, never thought about it helping to fight turbo lag. interesting.

If you had a stage four clutch or something outrageous you could just leave your foot on the gas the whole time while shifting. That way you could really fuzz up your gears.:icon16:

here is a link for double clutching & heel-toe shifting - that lame F&F movie done fucked everything . . . . . http://www.driftsession.com/drift_techniques/heeltoeshifting.htm

double clutching is not a waste, thats what saves the transmission under racing conditions

It's not bad for the car at all but it won't mke you any faster or anything. You'll beat other cars even worse if you just shift really quick by just using the clutch once.

Actually its quicker not to use the clutch at all. besides starting off from a stop:icon16:

shifting "really quick" is not good for the tranny - it should be semi-quick & not slammed into gear - even though its seems fun

what do u mean not using the clutch at all????

exactly what I said -

accelerating release gas slightly & rev match in neutral- then shift.
downshift bump the throttle to rev match while in neutral during the downshift. everything has to perfect for this to work

knowing your car helps - i dont recommend trying for the 1st time in your own car - it takes practice as does heel-toe down shifting with double clutching

you have sinchros in your tranny. You would be wasting time between shifts

Its all what you prefer. Some prefer clutch & some dont. Some can do it quicker with the clutch while others do it quicker without . . . . . I think your wasting time & power by pressing the clutch - you will be wasting tons of time if you cant shift properly without the clutch. Under racing condition you want to engage the clutch as little as needed if you must use that thing:wink:

If it were up to me all cars would have a sequential gearbox with paddle shifters. Finger clutch & foot clutch for 1st

make sure you are not granny shifting! haha :biggrin:

ps fast and furious causes at least a tenth of a second slower et!!!

Double Clutching actually wastes more time than just slam shifting but it does keep the rpm's up in the gear making for sooner shifting, but there's not much gain from double clutching and if you really want to tear the shit out of your tranny then try straight shifting with no clutch.