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Discussion Starter #1
Just wondering if any of you 5-speed G drivers apply the driving technique of double (de-)clutching when you downshift - AKA 'matching revs'?? I guess with the limited slip differential and synchromesh transmissions in the newer Gs this is even more do-able??

Has it been technically proven to save 'wear and tear' on the transmission??

<CosmicG thinks and grins in silence>....I just remembered in Fast and the Furious when Vin Diesel said "...granny shifting, not double-clutching like you should..." after a drag race - I don't think so!! Would have been in context at an auto x or in a rally race.
 

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Yeah, you should match revs when you downshift. You don't have to double clutch on any normal car though. To downshift, just put the clutch pedal in and blip the throttle then shift and let go of the clutch pedal. When done properly, it should be one smooth motion that doesn't slow down the car. You'll know when you do it right.

If you don't match the revs when downshifting, the car will slow down from the engine. Logically, there is less stress on the engine if you match the RPM's because the engine doesn't slow the car down.

The engine moves the car, the brakes slow down the car. I don't think it's a good idea to be engine braking normally.

Hah, TF&TF. Motec Exhaust? I still don't get what happens to the Eclipse in the first 5 minute 1/4 mile race. Did the floor blow off?? Haha..
 

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CosmicG20T said:
<CosmicG thinks and grins in silence>....I just remembered in Fast and the Furious when Vin Diesel said "...granny shifting, not double-clutching like you should..." after a drag race - I don't think so!! Would have been in context at an auto x or in a rally race.
That is in the context of being stupid, just like the rest of the movie. Cool cars, but the things they said......
 

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Similarly known as "Heel Toe" when used in a cornering racer context if you want to bring the brakes into it and get all hardcore:cheeky:

Actually no... i guess that is quite different huh?:p
 

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My dad had a Alfa Romeo Alfetta and you had to double clutch no matter what. You can tell if you match the engine speeds up close the turns will give a chrip. I love to double clutch with the exhaust and intake it sounds sweet.
 

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Double clutching is for people who can't shift right the first time.

Okay, that was kinda controversial. Honestly, you don't NEED to double clutch. It's just an old technique used when trannys weren't all nice and advanced like they are now. I think it's more of a placebo effect "look i'm shifting better cuz i'm working harder to shift."
 

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Discussion Starter #10
2nd nature I guess then...

On most occasions I double-clutch already...think it goes back to all that driving and racing back on the London streets in England and countryside rally tracks - here in Toronto, the roads are less windy, more grid layout, so its not as appropriate. 'Double-clutching' and 'heel and toe', it's all good.

When coming up to traffic lights, some times I would just shift into neutral, and let it slow down by itself, of course I would touch the brakes just so that the drivers behind me 'know to slow down'. There's no harm to the engine or transmission in doing this? (it saves gas..hehhehee).

Back to F.a.t.F - the story line was cheesy, but the cars were awesome, they could have done a more detailed spot on each of the cars they showed - perhaps on the DVD bonus materials.
 

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Re: 2nd nature I guess then...

Mike.Com said:
Yeah, you should match revs when you downshift. You don't have to double clutch on any normal car though.
Bingo.

CosmicG20T said:
On most occasions I double-clutch already...think it goes back to all that driving and racing back on the London streets in England and countryside rally tracks...


Double clutching is a old technique that was required for non-synchromesh gearboxes. Racing schools even teach you that it's totally unnecessary.
 

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Hah, I remember after the Fast and Furious came out. There were so many threads on the RX7 forum regarding double clutching it was getting annoying. :p

Here's some more threads regarding it if you're interested:

what is double clutching and heel and toeing??

Double clutching.

Double Clutching

Some people on that forum don't know what they're talkinga bout either. But whoever says:

"It's only for non-synchromesh transmissions; you don't really need to do it for most modern transmissions with synchros."

...is right. People tend to believe things from movies so they dismiss the easy but obvious answer. It's like clutchless shifting. You can shift smoothly at the right points without using the clutch but there's no benefit. Stupid F&F haha :D
 

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DC'ing my GT

I'd agree you don't have to do a true double clutch, although I do it by habit now. A point to think about: If proper rev matching through double clutching allows you to shift a non-synchro tranny and a tranny with a failed clutch, would that mean under NORMAL circumstances, double clutching and rev matching produces the least amount of stress on the tranny? I DISAGREE whole heartedly with the notion that a person who double clutches does not know how to shift. Try driving a Toyota Celica GT-S with a bad 2nd and 3rd gear synchro, that will test your shifting smoothness.
Matching the revs is the most important, you are matching the gearbox speed to the engine speed and, therefore, reducing wear on the clutch. The car mags discussed it sometime ago in a letter to the editor. Their conclusion was only use the double clutch / rev matching approaching a turn to get into the gear you need anyway. Any REV matching from say 5th to 4th to 3rd to 2nd and 2nd through the corner just ADDS wear to the pressure plate and throw out bearing. Also, do not downshift to slow the car, brakes are alot cheaper than a clutch. Simply, let off the gas and engine brake / pedal brake with the gear you are in until about 2000 or 1500 rpm, then shift to neutral and come to a stop.
Additionally, engine braking does not hurt a car, just use the gear you are already in or the gear you need after the turn.
 

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heel and toe

freaktroll said:
Similarly known as "Heel Toe" when used in a cornering racer context if you want to bring the brakes into it and get all hardcore:cheeky:

Actually no... i guess that is quite different huh?:p
You were right, heel-n-toe is part of double clutching / rev matching. If the pedals are properly spaced you can put the ball of your foot (just below your big toe) on the brake and the right side of your foot on the gas. The old days you would actually put the HEEL of your foot on the brake and your TOES on the gas which is now virtually impossible to do, so just the name carried over.

Heel and toe actually comes in handy if your engine has a malfunction and wants to quit when you let off the gas. You can brake and keep the revs up at the same time.

You want to see some REAL clutch work?!! Watch Ricky Rudd at Watkins Glen or Sears Point, the "foot" camera in his car shows some fastastic clutch/brake/gas "tap" dancing.
 

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Why the hell do you want to double the clutch on a modern car that has a syncromesh.You only needed to double clutch on old cars that don't have a syncromesh gearbox.All this stuff in the movie's is a load of old rubbish any way,what do they know.I can understand having to blip the throttle on a bike cos the revs drop so quickly.So if you can drive properly neednt do anything fancy to make your driving look good.When i was a kid my old man taught me to change gear without using the clutch at all, just listen to the engine note and change up just at the right time.
 

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Re: heel and toe

95Gee20Tee said:
You were right, heel-n-toe is part of double clutching / rev matching.
They are completely different things. The can be practiced together or separately. But heel and toe is not part of double clutching and double clutching is not necessarily a part of heel and toe.

95Gee20Tee said:
The old days you would actually put the HEEL of your foot on the brake and your TOES on the gas which is now virtually impossible to do, so just the name carried over.
Wrong.
 

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GT UK said:
Why the hell do you want to double the clutch on a modern car that has a syncromesh.You only needed to double clutch on old cars that don't have a syncromesh gearbox.All this stuff in the movie's is a load of old rubbish any way,what do they know.
Bloody right mate!
 
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