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Stupid question.. what is double clutching???

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Old Aug 12, 2003 | 12:06 PM
  #1  
Kuth678's Avatar
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Car Info: 2004 2.5TS manual
Stupid question.. what is double clutching???

I've driven standards for about 10 years now. I rev match on all my down shifts and I never shift hard between gears. I thought I was doing all I could to treat the transmissions nice.

But I've heard many people talk about double clutching. The only thing I know about it is that it was necessary on old cars without syncros. Why would I need to do it on a modern car.

More importantly HOW is it done?

Hec, while I'm asking. How does one "Heel and toe"?
Old Aug 12, 2003 | 01:20 PM
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Now you made me all curious - 13 years in sticks and never heard of 'double clutching'.

Quick search on Yahoo turned up this article which seems to explain it thoroughly.

I can't verify the technical stuff because it's beyond my current knowledge, but his layman's summary was interesting...

Push in clutch Layshaft equals Third gear speed

Select Neutral Layshaft coasts

Let out clutch Layshaft equals engine speed

Blip throttle Engine and layshaft speed up to Second gear speed and a little

Push in clutch Layshaft coasts

Select Second No GRAUNCH if you have the speeds right. Ideally,
layshaft has coasted down to exactly Second gear speed

Let out clutch System is all locked up in Second.

Here's another article - had to include it cos it mentions Triumphs and MGs.
(This explanation is strictly in driver's terms)

Last edited by bonkers; Aug 12, 2003 at 01:25 PM.
Old Aug 12, 2003 | 01:57 PM
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Originally posted by XstephenX
Rev matching IS double clutching.
incorrect - rev matching is part of double clutching. You can rev match without double clutching. You can also double clutch without rev matching, although it going to do you almost no good at all on a downshift.
Old Aug 12, 2003 | 08:48 PM
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Now you see why I was so confused about it.

So would double clutching be

1. Press clutch and remove from gear
2. release clutch while in nuetral
3. press clutch and then rev match
4. put car in next/previous gear and release clutch

????

Still, unlike than rev matching on down shifts, I still see no point in pressing the clutch twice. Only old cars w/out snycros needed that.

Anyone help me out here. I'm by far not the best driver in the world, so there has to be someone who can tell me what, if any, good it does on a new car.
Old Aug 13, 2003 | 08:09 AM
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ahhh my brain...i just woke up...ok can you take the car out of gear without depressing the clutch? i heard somewhere you can
Old Aug 13, 2003 | 10:29 AM
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http://www.hondalife.com/modules.php...rticle&artid=3
Old Aug 13, 2003 | 10:41 AM
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Originally posted by rodon
Forget what xstephenx says; you don't have it quite right.
That's good advice, well meaning people often don't have all of their facts straight.

Rodon is correct - you need to match the engine speed to the road speed for the gear you intend to go into with the clutch released (up) while in neutral. So on an upshift, all you have to do is release the clutch in neutral for a quick second, depress the clutch again and the gear shifter will get sucked into your next higher gear. It will feel different (smoother) than just clutching in and upshifting, although it is really not at all necessary unless you are driving a car with worn out syncros.
The downshift requires a little more practice. You will need to give some gas while in neutral with the clutch engaged, which is a little trickier. When first learning, the tendency is to not rev the engine high enough on before the downshift. Practice both blipping as well as gently holding the gas pedal. I prefer the holding of the gas pedal method, blipping can be faster and is more "race car driver" but for a smooth downshift into first going into a parking lot, holding the gas works better for me.
This technique is helpful to downshift my WRX into first from a roll, althought I can also do it if I just rev match, without the double clutch, but it takes longer.
Old Aug 22, 2003 | 03:28 PM
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ahhh my brain...i just woke up...ok can you take the car out of gear without depressing the clutch? i heard somewhere you can
awns,

You can drive a manual tranny car without the clutch at all - takeoff, upshifting and all if you really, really haftoo.

J
Old Aug 30, 2003 | 08:25 PM
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exedy light flywheel makes this sooooooo much fun....



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