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for me, it's habit, how about you?[/b]
Never really found a use for it. Rev-matching only during heavy traffic, and double clutching during spirited acceleration, but thats it.

Not a habit, but used.
 

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Discussion Starter #4
Double-Clutching is a waste of time in a syncro-meshed transmission, IMHO. But I certainly rev-match on every downshift.[/b]
I'd disagree, IMO. At high speed getting the sychros to open up (as nine coronas mentioned) is hard at the best. For example, at TWS coming into turn one you're running 120-130 and braking, turning in at about 100-110 looking for 4th gear, I'd challenge anyone to downshift into 4th at those speeds! The sychros will usually lock you out of that gear as you're close to redline. Double clutching and matching revs allows it. But again it's my POV so take it or leave it...

I'd agree that day to day driving doesn't require it, but it's still useful for the practice

like I said, my 2 cents
 

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Do you guys usually shift down through all the gears? I usually just go down to about 3rd sometimes 2nd all the time. How about when you guys rev match downshifting gears when breaking? Do just match it with your heel, or do you use your left foot to break, and right foot to match?

I don't ever double-clutch, like Sigma said, it's a waste of time. What's your guys techniques for double clutching?
 

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I rev match, but don't usually double clutch. I find that even under the hardest of downshifts, if you match revs, the syncros will still work perfectly.

I downshift 5th through 2nd. I use the left foot on the clutch and the right foot to break when breaking is needed.
 

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I'd disagree, IMO. At high speed getting the sychros to open up (as nine coronas mentioned) is hard at the best. For example, at TWS coming into turn one you're running 120-130 and braking, turning in at about 100-110 looking for 4th gear, I'd challenge anyone to downshift into 4th at those speeds! The sychros will usually lock you out of that gear as you're close to redline. Double clutching and matching revs allows it. But again it's my POV so take it or leave it...

I'd agree that day to day driving doesn't require it, but it's still useful for the practice

like I said, my 2 cents[/b]
Well, I can't speak for the MS6 transmission, but every other synchro-meshed manual I've driven has no problem engaging any gears no matter how close the resulting revs will be to redline as long as your rev-match was good. The sole exception to that would be dropping into 1st gear which is often very difficult to engage in most cars over about 10mph unless you double-clutch.

If you feel it helps, more power to ya. It's certainly saving a little bit of wear on the synchros. I just don't feel that it's worth the time and effort when I can otherwise get it into smoothly into gear (with perhaps a slightly greater wear on the synchros) without doing it.
 

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I never double clutch, but I rev match all the time.
 

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Discussion Starter #9
Well, I can't speak for the MS6 transmission, but every other synchro-meshed manual I've driven has no problem engaging any gears no matter how close the resulting revs will be to redline as long as your rev-match was good. The sole exception to that would be dropping into 1st gear which is often very difficult to engage in most cars over about 10mph unless you double-clutch.

If you feel it helps, more power to ya. It's certainly saving a little bit of wear on the synchros. I just don't feel that it's worth the time and effort when I can otherwise get it into smoothly into gear (with perhaps a slightly greater wear on the synchros) without doing it.
[/quot

You're right, the WHOLE purpose of synchromesh tranny is to avoid double clutching. However, it does not mean that it is the best way to do it. The only reason I do it is habit. I used to ATX a 240z and that tranny needed a double clutch to engage gears at high RPM. That said, if you do a Skip Barber series race, you'd damn well better to be able to DC as those are not synchronized.

Put it this way, all race drivers know how to DC. Since they know how and do, is it not something to consider?

PS how's the weather there in DFW? it's like 34 here and about to ice over!
 

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My argument....

Try WOT launch through 4th+....

1st - 2nd is usually no problem but at high RPM / Redline double clutching makes it impossible to get locked out or miss the gear.... 2nd - 3rd... just about all speed6 people have a hickup problem under heavy throttle right at the start.. double clutching helps reduce this.... 4th-6th... doesn't require it usually....

Anyway... its good practice... and I think many people use it when needed... though say you're pulling into heavy traffic on the freeway... (traffic going 70+)... and you have to get infront of a semi or something... OR.. slam your breaks on and wait for it to pass... people who don't practice double clutching will probably forget.. and have issues slamming through gears at high-rpms... while those who do it often... will be paying more attention to traffic.. and less to getting it into the proper gear.. and worrying about the syncros...
 

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Double-Clutching is a waste of time in a syncro-meshed transmission, IMHO. But I certainly rev-match on every downshift.[/b]

Totally agree here ... with today's syncro technology .. you really don't have to do this ..

Crowley
 

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I can't downshift right at all.....My engine stays jumping LOL
 

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Its sucks to say im a noob. This is my first stick shift car and now it is in the shop as some of you know what happened to my car and saw my post. But yea i only have 1500 miles of manual transmission in play, and i have no clue what you guys are talking about with the "heel toe" thingy.lol I knwo what your talking about with the rev matching when downshifting but im to afraid to try that i think i'll porb break my car or something. I wish i did not know how to do all that though sounds very interesting. Anyone live around the north jersey area that doesn't mind showing me all this shifting technique stuff it would be greatly appreciated. And hopefully i get my baby roxanne back soon, i miss her :(
 

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I rev match whenever I downshift (toe and heel if braking), but I only rarely double clutch, especially when BRAKING.

Rev matching has become a habit now though, so I guess that's good. I don't notice a difference between double clutching and just normal rev matching (I guess arguably there's less strain on the synchros).
 

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He's driving a Chrysler!
 

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Its sucks to say im a noob. This is my first stick shift car and now it is in the shop as some of you know what happened to my car and saw my post. But yea i only have 1500 miles of manual transmission in play, and i have no clue what you guys are talking about with the "heel toe" thingy.lol I knwo what your talking about with the rev matching when downshifting but im to afraid to try that i think i'll porb break my car or something. I wish i did not know how to do all that though sounds very interesting. Anyone live around the north jersey area that doesn't mind showing me all this shifting technique stuff it would be greatly appreciated. And hopefully i get my baby roxanne back soon, i miss her :([/b]
Edit: I was tired earlier today and got the heel and toe positions reversed. You'd have to have a double jointed ankle to do it the way I explained it. Sorry for the brain fart. Corrected now.

Heel and toe is where you rev match while braking (so downshifting while braking). It's done by angling your right foot so that the heel engages the accelerator pedal while the toe of the same shoe engages the brake pedal. You independently modulate the throttle with your heel to rev match the downshift. Braking is done with the toes.

Double clutching is also for downshifting and is when you release the clutch pedal twice during a downshift. The first time is when the transmission goes into neutral (as in a 3 > Neutral > 2 downshift). This spins up the gears and shafts in the gearbox so that everything is nicely in sync when shifting into 2nd. Final clutch release is when fully in 2nd. It looks like this for a 3rd gear to 2nd gear downshift:
Press clutch pedal in > shift from 3rd to Neutral > release clutch pedal and blip throttle to get revs slightly past point where gearbox would be if in 2nd at that speed > press clutch pedal in > shift from Neutral to 2nd > release clutch pedal.

Sounds complicated but with practice it becomes second nature. Real challenge is to combine heel and toe together with double clutching. This takes a lot of independent heel and toe motion along with clutch foot and right shift hand, usually while steering too (this should be done before entering corner but ...).

To answer the original question of this thread, I used to double clutch in some of my previous cars ('70s and '80s) but I haven't really practiced it in years. I do once in a while just for the heck of it, but I'm sloppy and out of practice.
Most modern transmissions with full synros are so good that with some attempt to rev match the shifting is smooth and effortless. As already explained in this and other threads, double clutching was a skill necessitated by early transmission designs without syncros. Downshifting without double clutching would put un-necessary stress on easily broken gearbox parts and/or disrupt the balance of the car as low engine revs exert an instant engine braking on the back tires (older cars with non-syncro gearboxes were typically RWD) possibly causing a spin (aggravated further by the toe changes in the antiquated rear suspension designs when weight shifted forwards due to mismatched downshift).
 

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I'm a pro at double clutching in my Neon, but the MS6's a wee-bit tricky. It takes it a lot more effort to keep it smooth.
I've practiced heel-toe quite a bit in the Neon. It takes qui te a bit of coordination and concentration.

**EDIT:
Ah! Forgot to mention I double clutch mostly while braking. Doing so is actually much quicker than the snychromesh in the Neon, and it's 100% smoother.
 

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I don't double clutch. But I'm getting pretty good at rev matching downshifts. And I am practacing as well, "heel toe" downfhifts, although I don't use my heel and my toes, I more use my big toe over the brake and my little toe rev matching the gas.
 
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