Stupid question.. what is double clutching???
08-12-2003, 12:06 PM
#1
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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"?
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"?
08-12-2003, 01:20 PM
#2
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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...
Here's another article - had to include it cos it mentions Triumphs and MGs.
(This explanation is strictly in driver's terms)
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.
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; 08-12-2003 at 01:25 PM.
08-12-2003, 01:57 PM
#4
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Originally posted by XstephenX
Rev matching IS double clutching.
Rev matching IS double clutching.
08-12-2003, 08:48 PM
#6
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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.
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.
08-13-2003, 07:58 AM
#7
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Yes that is double clutching. And rev matching is double clutching unlike what BlingBling said. You can't rev match without having the car in neutral, which would mean double clutching. I knew what I was trying to say, and what you just said is right. It is clutching to neutral, then rev match, then clutch to gear.
Stephen
Stephen
08-13-2003, 09:18 AM
#9
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Originally posted by Kuth678
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.
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.
Here you go, one more time:
1. press (disengage) clutch
2. shift to neutral
3. release clutch
4. blip throttle
5. press clutch
6. shift
7. release clutch
You still need to "rev match" when releasing the clutch @ 7 to avoid jerking. But double clutching is used to shift a synchroless (dog-geared) transmission, or save wear on synchros if you have them. Rev matching is to eliminate the herky-jerkies. Two different things entirely.
08-13-2003, 09:22 AM
#10
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Originally posted by awns729
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
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
08-13-2003, 09:43 AM
#11
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I've been doing it as rodon describes, in my 5mt Escort with 214,000 miles and no tranny problems. With that wimpy 1.9l engine, I would enjoy "depth in the gearbox" - meaning, at a speed like 45 or so, I can choose to pop it down to fourth, third, or even second, for a burst of speed.
I learned this technique on unsynchronized Ford tractors (1000 & 3910), driving on the Ohio State campus. Most other operators would just put them in 5th and go, they were afraid to shift.
My 98 OB will not allow me to downshift into first without doing this, even at a slow walking speed.
And that comment about popping it out of gear without the clutch if there is no load is correct. Try this: from a steady speed, put a light pressure on the gearshift, trying to push it into neutral. Lighten up on the throttle, and when there is no load, the shifter will pop into neutral effortlessly.
It is also possible to go into gear from neutral at speed without the clutch, too, but you have to match the revs almost perfectly, or else CRUNCH.
I learned this technique on unsynchronized Ford tractors (1000 & 3910), driving on the Ohio State campus. Most other operators would just put them in 5th and go, they were afraid to shift.
My 98 OB will not allow me to downshift into first without doing this, even at a slow walking speed.
And that comment about popping it out of gear without the clutch if there is no load is correct. Try this: from a steady speed, put a light pressure on the gearshift, trying to push it into neutral. Lighten up on the throttle, and when there is no load, the shifter will pop into neutral effortlessly.
It is also possible to go into gear from neutral at speed without the clutch, too, but you have to match the revs almost perfectly, or else CRUNCH.
08-13-2003, 10:41 AM
#13
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Originally posted by rodon
Forget what xstephenx says; you don't have it quite right.
Forget what xstephenx says; you don't have it quite right.
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.
08-22-2003, 03:28 PM
#14
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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
You can drive a manual tranny car without the clutch at all - takeoff, upshifting and all if you really, really haftoo.
J
