I do this insted of double clutchin .. ok? [Archive]

djm221

02-07-2002, 11:28 PM

Originally posted by GTS LAID
if he rev matches while letting out the clutch then it WILL wear it cause he's not doing the rev matching entirely but the clutch is...
If he gives it the gas to rev where that downshift will be, it shouldn't put any strain on the clutch, that is, if you do it right.
Like I said, and someone better agree with me, double clutching is to save the synchros, or lack thereof.

GTS LAID

02-07-2002, 11:34 PM

you're completely right.. and i do it for that reason.. but sometimes i mess up and i press in the clutch the second time too quickly while i'm still gasing it and you can tell that you're doing some wear... no disagreement.. just clarification.. just dont press both at the same time.. hehe.. unless the clutch is all the way in.

BRAK

02-08-2002, 06:30 AM

YA i rev match quickly while in all the way in (totaly dissabled)
then ease up on the clutch. Ya i do the same think when i double clutch ... i tap it to hard to fast ... and i feel that wear soooo i do get nervous while learnin it and stick to my method. I am a very defensive driver so i tend to rely on the brake to slow down then dod what i do ... insted of double clutching. BUT when the flag goes down i get offensive LOL . that is at the track ... no illegal racing here .... not worth the risks.

PapiChuu

02-08-2002, 07:45 AM

i agree with dj :stupid:

jer925

02-08-2002, 09:57 AM

no matter how you spin it its going to wear the clutch and synchros. the synchros are there for a purpose so why not use them. class 7 and 8 trucks don't have synchros in the transmission cause they would have to be as big as the truck to handle the torque. if your going to mess around like that just don't use the clutch at all and rev match. atleast you would only be wearing one part instead of two. be careful cause all the synchros are is a brass ring with teeth on it and if it becomes worn exsseivly the car will start jumping out of gear. just got done doing a t-10 borg-warner 4 speed tranny.

kabal57

02-08-2002, 01:38 PM

so rev matching with the clutch fully engauged while downshifting is bad? i've always done that in all my cars, never had to have any clutch work done tho... is it bad for the tranny as well?

GTS LAID

02-08-2002, 01:42 PM

what are you talking about "dont use the clutch at all" just pop it out of gear you mean? well either way double clutching a downshift will outsmooth a regular downshift anyday if done right... if you wanna find out if you're good... go to 50 (in the gts) in 5th and then double clutch 5-4-3-2 ... i've been practicing and you cant tell that i'm shifting if the stereo is loud and you're not looking... believe it or not the up shifts are harder to make smooth after double clutching down.. i think the inertia of the flywheel and the nimbleness you need to dc down isnt needed when going up.. you just have to wait enough for the revs to drop to the right pointbefore re-engaging the clutch.

BigBad91Turbo

02-08-2002, 01:48 PM

Oh My God....You guys kill me!!!

This is the First post on this forum I have read....Oh My god...

Seriously guys, put the fast and the furious DVD back on the shelf and pretend that you NEVER saw it. Yes I love the movie....but please....what do you think? that Vin's statement at the first race "granny clutching, not double clutching like you should" is correct. That is purely move crap.....

Double clutching is something that is done in big rigs with huge gear spans to assist gear engagements...not little celica with tight 6sp tranies. If you are double clutching you are wasting time, and loosing on time that you should be engaged (motor to flywheel to clutch to trany to skip a few ...wheels...)

So the bottom line....your shifts should be quick and precise. The challenge is (especially on a stock clutch) not to be producing more power than the clutch can handle, eventually spinning it. This creates a lot of heat which is the biggest enemy of a clutch. That is how you will burn out your clutch.

I run a race clutch set up on my supra and when running the 1/4 my foot is down the whole time, I just slam throught the gears, now mind you I have a 6 puck, carbon clutch, blowoff valves and a computer controlled rev limiter (nothing like what is in the celica).

GTS LAID

02-08-2002, 02:10 PM

actually double clutching down before going into a turn can help you going in cause it doesnt unsettle your drivetrain or your suspension... and i only saw FnF in the movies and thought it was ok better than 60 seconds...

as for you... well if you dont wanna add to the conversation then just read and make believe we have a big rig.

BigBad91Turbo

02-08-2002, 02:46 PM

You sure you do not mean rev matching, Double clutching??, go to any SCCA event and find somebody double clutching (real double cutching) I do not think so.

I have had a trany that used dog cut gears and I never had to bother with double clutching, double clutching is an urban myth..

to double clutch you would have to reseale the gas, then push the clutch in, shift to neutral, release the clutch agian, press the gas to rev, release the gas, depress the gas agian, the engage the clutch, then shift into gear, then release the clutch, then give gas...

As for adding to the conversation..
God forbid somebody posts to tell you guy you are doing something wrong...And yes I do race, both my Supra and My Celica GTS, and yes I mean organized event racing (SCCA) and have been racing for over 10 years. Infact I have even been a performance driving instructor so yes I do feel a little versed on this subject.

zMaN

02-08-2002, 04:28 PM

So BigBad you are saying rev matchig is not necssary? I have heard the Syncros in the GTS are prone to wear. How can I keep from wearing out the syncros?

BigBad91Turbo

02-08-2002, 06:32 PM

No Not At All!!!

You should be rev matching as much as possible. Dropping into lower gear and forcing your engine to match up is very hard on the hole car, all that energy comes from the tires, through the driveline...blah blah... to the engine. Hit that gas rev it up a little and smoothly engage. Not rev matching is bad because you are essentially engine bracking, you will loose speed, and more importantly possible break traction while in a corner. GTS laid has the right idea I think we he reffers to not wanting to unsettle your drivetrain or your suspension. I am reallyu wondering where he got this double clutching idea, I really am not even sure if he really knows what it means.

All I am saying is that Double clutching is wrong and slow. Put the clutch in, tap the throttle a little bit to jump it up an smoothly disengage the clutch. Nice an simple.

pokgai

02-11-2002, 11:31 AM

i think that is what the japanese do too.

after watching a lot of videos, when they approach a turn, they do this:

push the clutch in with their left foot. with their right foot's toe, they push the brake, with their heel they blip the gas (heel-toe). all while downshifting. and they get it down SMOOTH. ive never seen them double clutch.

ive attempted double clutching and heel toe. it is very hard. but heel toe-rev matching is good. i just dont always get the exact amount of matching (usually a little too much).

one question. is engine braking safe? liek when slowing down, using the brake AND downshifting without rev matching? to help slow down? what about leaving it in 5th gear and slowing down to about 10 mph then going to N?

bgreganti

02-11-2002, 12:31 PM

Originally posted by BigBad91Turbo
Oh My God....You guys kill me!!!

This is the First post on this forum I have read....Oh My god...

Seriously guys, put the fast and the furious DVD back on the shelf and pretend that you NEVER saw it. Yes I love the movie....but please....what do you think? that Vin's statement at the first race "granny clutching, not double clutching like you should" is correct. That is purely move crap.....

I like this guy already! Welcome to the board Chris.

BRAK

02-11-2002, 03:51 PM

TY all for the advise and NO .... i didnt hear the double clutchin from FnF. I heard it on some BMW / HONDA chat boards i was reading a LONG time back.
Givin this is my first manual car ... i wanted to ask rather than not do it right.
Belive it or not but i have learned allot from just this post , and i feel comfortable now with the way im driving. TY everyone for the comments.

BigBad91Turbo

02-11-2002, 05:58 PM

Somebody asked if engine braking was good above....

Long story, Yes and no.

In an offroad vehicle there are loss of times you would it to help maintain tire traction such as when going down a hill.

On a celica, or most any car for that matter...well it really depends. For most of the driving you will ever do, DO NOT brake with the engine. To put it simply, that is alot of stress on the drivetrain and engine. Will it all take it, yes, for a while. But lets look at economics... How much is an engine job?, how much are brakes. Well, brake pads are cheap and easy to service and save your enigne, seems like an choice.

Now, for racers on a road course, all that can go out the window, again if you race for a team that pays for the car you are destroying. Often times some racers will use the engine to brake them down before going into some of the turns. Understand why, this is NOT for performance reason, well not exactly. In a long road race, brakes are as important, if not more than power. the ability to save your brakes and let them cool is vital to allowing them to attack the corner at a higher rate of speed and brake late. If they can manage a corner with some engine braking they will to reduce the heat produced. But agian they have cars that are paid for and get there engines rebuilt all the time.

That is money that I do not have!

zMaN

02-11-2002, 07:40 PM

Being from a cold weather state I can think of another reason to use engin breaking. I live on a VERY steep hill and when we have heavy snow or an ice storm leaving the car in second gear and coasting down the hill works much better than using the brakes. The breaks are more likely to go into anti-lock mode and not slow me down enough. Now plese note that I don't speed up and then let the engine slow me down. I simply let the engine KEEP me slow.

SlickCar

02-12-2002, 06:14 PM

Hey PokeKai !!
I know exactly what you're talking about..
yeah.. the Pros in the video doesn't double Clutch at all..

they just Rev match ........

The video is Best Motoring yeah?

OMG... Have not posted for so long !!
arr..

STill luv my Silver GTS though.....

BigBad91Turbo

02-12-2002, 06:46 PM

Originally posted by zMaN
Being from a cold weather state I can think of another reason to use engin breaking. I live on a VERY steep hill and when we have heavy snow or an ice storm leaving the car in second gear and coasting down the hill works much better than using the brakes. The breaks are more likely to go into anti-lock mode and not slow me down enough. Now plese note that I don't speed up and then let the engine slow me down. I simply let the engine KEEP me slow.

That is exactly what I was refering to when I was talking about offroad driving....but i was too lazy for to type another paragraph :-)

I am from orrignally from Canada, man I remember when ever snow started falling, I would find any excuse to borrow my dads car..., I think I was the snow drift king, both drifting, and going into them....

Sonic

02-13-2002, 05:37 PM

Considering I've gone through two synchros and a new transmission, I would say double clutching is an EXCELLENT idea.

No, I didn't abuse the car nor did I race it - Toyota Corporation agreed with me and I had no hassles getting replacement parts.
With that said, this tranny is still very delicate...I have '02 in a '00 GT-S (all the same though).

Sonic

BigBad91Turbo

02-14-2002, 01:22 PM

Considering I've gone through two synchros and a new transmission, I would say double clutching is an EXCELLENT idea.

The issue is clearly expressed above as to why you do not double clutch.

Sorry but you just downgraded yourself to a ricer in my books. Where on earth did you get this notion on double clutching?. Go actually learn about driving instead of pretending too and you will quickly learn.

Double clutching is a myth perpetuated by so called street racers AKA 'ricers'.

Unity112

02-14-2002, 03:00 PM

Let me play as the devils advocate for a little bit. But before I get started, I totally agree that double clutching is unecessary when racing a car that utelizes synchromeshes. Unless its a long endurance race, the wear will be minimal with correct revmatching.

Now BigBad91turbo, dare you call Carroll Smith a ricer who writes about this double clutching myth? How about assorted authors who write different books? Haven't read Skip Barbers book, but I would imagine that he has mentioned about the use of the double clutch. Back in the older days when cars didn't have synchros, this was the only way that racers could downshift without hearing that godawful scratching noise or losing that gear. It isn't always necessary in most racing situations, but yet is a good skill to have IMO.

Oh and for the FnF boys. Double clutching in a drag race will help you win a free look at the backside of the other driver's brake lights. :)

BigBad91Turbo

02-14-2002, 09:13 PM

Unity...yes you are correct about the old days when double clutching was used. I have to double clutch one of the old firetrucks I have at my station to get it into gear without grinding.

But like you said, it is not needed on any modern car. I really would like to see a wining racer who uses that technique, once I see that I will be convinced. I have attended many driving courses in by earlier days, never have I ever had any instructor advocate double clutching.

Now that said, I really think a lot of people do not really know what double clutching is, even though they may advocate it. I think a lot of people get rev matching confused with d-clutching.

As you likely know, you can really just not use the clutch if you can play with gas peddle correctly for up and downshifts.

zMaN

02-14-2002, 10:20 PM

Originally posted by BigBad91Turbo

As you likely know, you can really just not use the clutch if you can play with gas peddle correctly for up and downshifts.

this is very true. back when I was in Highschool I drove a '83 toyota tercel. One day when I was in town my clutch pedal broke. The pedal had plastic teeth that would catch on similar plastic teeth that were on a part that was connected to the clutch. It was to keep people from riding the clutch I guess.

Well the pedal broke and I , being in highschool, was broke so I could not call for a tow. I put the car in 1st gear and strted it in first. Car took right off. Then I rev matched to shift into all the gears. I grinded a few but I got most of my shifts. Every time I had to stop at a light I would have to turn off my car and put in in first, then start it in 1st to take off. It was an interesting trip home. :)

GTS LAID

02-14-2002, 11:06 PM

i was trying both techniques for a good half hour on my way home... i think you guys are right about rev matching...

to dispel any other qualms.. can you guys answer me these questions:

1) I noticed that the revs climb faster when the grarbox is in neutral and the clutch pedal is up as opposed to when the clutch pedal is depressed and I'm simply rev matching... whats the difference in the two scenarios and why in the world would the flywheel spin slower if its disengaged in both cases.

2) it might be that i just need to practice rev matching a bit more but I've noticed that drivetrain loading going into a turn is done much easier on a double clutch rather than a rev match.. i think it might be b/c im overly worried in a rev match situation that since my gasing it and clutching are occuring so close to each other that i might screw up and gas it while the clutch is half engaged...

3) I dont know if you guys have read the article on driving manual cars written by that BMW dude a couple of years ago but its got some good information about both techniques and I think it advocates each equally... which is again why I dont think its simply a stupid or ricer thing to do...

with that i'm gonna do a bit of research as to the diff. between the clutch pedal positions in diff gears and get back to you guys.