What is Double-Clutching?
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Originally posted by imPHOrt racer
Anyone want to race my Integra? I wont even speed shift, double clutch or whatever you guys claims help ya, if ya got a fast car ya got a fast car....60% driver 40% car I believe, most people think 90% driver 10 % car if ya believe that take me on with a 7th gen, or hey maybe even a Type R if ya want hehe
Anyone want to race my Integra? I wont even speed shift, double clutch or whatever you guys claims help ya, if ya got a fast car ya got a fast car....60% driver 40% car I believe, most people think 90% driver 10 % car if ya believe that take me on with a 7th gen, or hey maybe even a Type R if ya want hehe
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Blah blah . it's 50% 50%. I don't see Michael Andretti smoking people in a Geo Metro. On that same note, I see 16 year old kids in their parents Grand Prix smoking people left and right. Half driver, half car. .
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Rep Power: 0 omfg this is just turning into a flame war over something that doesnt really matter...
look the driver matters and so does that car, im gonna go with the 50 50 thing cause pretty much, if one goes one way, they both do... if i have a great car im gonna go fast, if im a great driver im gonna go fast...
and on another note, the guy that said earlier that double clutching would **** up your tranny, IS A TARD!!! if anything double clutching would prolong the life of your tranny. its easier on your synchro.
look the driver matters and so does that car, im gonna go with the 50 50 thing cause pretty much, if one goes one way, they both do... if i have a great car im gonna go fast, if im a great driver im gonna go fast...
and on another note, the guy that said earlier that double clutching would **** up your tranny, IS A TARD!!! if anything double clutching would prolong the life of your tranny. its easier on your synchro.
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Rep Power: 0 Since you are saying that it is more driver than it is car you are telling me that you can beat cars that are better than you???? Would you care to go up against a 69 Charger? I happen to have one in my garage if you think your Teg is so mighty powerful, I would like to sure you what power looks and sounds like
Double-clutching in a 7th gen civic:
Yes, you can rev-match when downshifting. But in technical terms, you only dbl-clutch if you want to d-shift into 1st (why you would do that, I don't know). The car doesn't let you downshift into 1st most often (unless you are going really slow). BUT, you can fool the car. In 2nd, and going slow, press clutch, rev to 3k or so, move shifter into 1st, clutch up. A/K/A rev-matching.
As I said, the car doesn't let you d-shift into first. But if you do this, it will let you shift into 1st gear because the rpms are high enough (as if you were shifting from 1 to 2).
Yes, you can rev-match when downshifting. But in technical terms, you only dbl-clutch if you want to d-shift into 1st (why you would do that, I don't know). The car doesn't let you downshift into 1st most often (unless you are going really slow). BUT, you can fool the car. In 2nd, and going slow, press clutch, rev to 3k or so, move shifter into 1st, clutch up. A/K/A rev-matching.
As I said, the car doesn't let you d-shift into first. But if you do this, it will let you shift into 1st gear because the rpms are high enough (as if you were shifting from 1 to 2).
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From: Toronto, Ontario, Canada
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as has been said many times, double clutching is not something that'll help your quarter mile time. those who think it does, and those who think it's bad for the tranny......you're.....very ignorant.
for cars with synchro trannys:
double clutching is not an accurate term. what is done is actually rev-matched shifting. It is ONLY DONE WHEN DOWNSHIFTING, to make the shift transition smooth, thus reducing the amount of wear on the clutch and tires. It can also be thought of as a precursor to learning how to heel-toe. Both are the same concept, one is simply done while braking.
Those who think it helps you in your drag time are mistaken. It CAN however help you in your cornering speeds, allowing you to turn at the limit of the tire's adhesion and accelerate out in the right gear that puts the engine in the power band, without taking traction away from the tires to spin the engine up to the desired RPMs.
I won't cover cars with un-synced trannies, like trucks/race cars as we don't drive them, but suffice to say THEY are the only ones that need to double clutch on both upshift and downshift. And even then, a good driver will only need to double-clutch on downshift, as when you are upshifting, the engine rpms and the input shaft rpms are both dropping, if timed right it will allow you to shift without double clutching.
as has been said many times, double clutching is not something that'll help your quarter mile time. those who think it does, and those who think it's bad for the tranny......you're.....very ignorant.
for cars with synchro trannys:
double clutching is not an accurate term. what is done is actually rev-matched shifting. It is ONLY DONE WHEN DOWNSHIFTING, to make the shift transition smooth, thus reducing the amount of wear on the clutch and tires. It can also be thought of as a precursor to learning how to heel-toe. Both are the same concept, one is simply done while braking.
Those who think it helps you in your drag time are mistaken. It CAN however help you in your cornering speeds, allowing you to turn at the limit of the tire's adhesion and accelerate out in the right gear that puts the engine in the power band, without taking traction away from the tires to spin the engine up to the desired RPMs.
I won't cover cars with un-synced trannies, like trucks/race cars as we don't drive them, but suffice to say THEY are the only ones that need to double clutch on both upshift and downshift. And even then, a good driver will only need to double-clutch on downshift, as when you are upshifting, the engine rpms and the input shaft rpms are both dropping, if timed right it will allow you to shift without double clutching.
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Rep Power: 0 one CAN do a true double clutch even on a synced tranny, it will save your synchros from stress.
complete description rev matching vs. double-clutching synced trannys:
rev matching:
1. disengage clutch
2. shift down one gear
3. rev engine to approx. the speed it would be running if you were driving in that gear at the current speed (e.g. in our cars, shifting into 2nd from 3rd travelling at 90km/h, you would need to rev up to about 6000 rpm)
4. re-engage clutch
double clutching:
1. disengage clutch
2. shift into neutral
3. release clutch -> this is the double clutching step. It hooks the engine up to the tranny and spins up the tranny's input shaft.
4. rev engine to approx. the speed it would be running if you were driving in that gear at the current speed (e.g. in our cars, shifting into 2nd from 3rd travelling at 90km/h, you would need to rev up to about 6000 rpm) -> done here, this step revs up the tranny's input shaft to the proper speeds. This is what synchros do. Doing it yourself with the engine saves wear and tear on the synchros.
5. disengage clutch -> this step can be thought of as optional, if you have it done perfectly you can actually shift into gear smoothly. I SERIOUSLY suggest you do it however, unless you are PERFECT at it.
6. shift down one gear
7. reengage clutch
done right, both will result in a downshift that is imperceptible. double clutching has the advantage that if done right, the shifting into gear will feel much smoother as well.
complete description rev matching vs. double-clutching synced trannys:
rev matching:
1. disengage clutch
2. shift down one gear
3. rev engine to approx. the speed it would be running if you were driving in that gear at the current speed (e.g. in our cars, shifting into 2nd from 3rd travelling at 90km/h, you would need to rev up to about 6000 rpm)
4. re-engage clutch
double clutching:
1. disengage clutch
2. shift into neutral
3. release clutch -> this is the double clutching step. It hooks the engine up to the tranny and spins up the tranny's input shaft.
4. rev engine to approx. the speed it would be running if you were driving in that gear at the current speed (e.g. in our cars, shifting into 2nd from 3rd travelling at 90km/h, you would need to rev up to about 6000 rpm) -> done here, this step revs up the tranny's input shaft to the proper speeds. This is what synchros do. Doing it yourself with the engine saves wear and tear on the synchros.
5. disengage clutch -> this step can be thought of as optional, if you have it done perfectly you can actually shift into gear smoothly. I SERIOUSLY suggest you do it however, unless you are PERFECT at it.
6. shift down one gear
7. reengage clutch
done right, both will result in a downshift that is imperceptible. double clutching has the advantage that if done right, the shifting into gear will feel much smoother as well.
Autocross Junky
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Rep Power: 380 Originally posted by gelshmoff
Double-clutching in a 7th gen civic:
Yes, you can rev-match when downshifting. But in technical terms, you only dbl-clutch if you want to d-shift into 1st (why you would do that, I don't know). The car doesn't let you downshift into 1st most often (unless you are going really slow). BUT, you can fool the car. In 2nd, and going slow, press clutch, rev to 3k or so, move shifter into 1st, clutch up. A/K/A rev-matching.
As I said, the car doesn't let you d-shift into first. But if you do this, it will let you shift into 1st gear because the rpms are high enough (as if you were shifting from 1 to 2).
Double-clutching in a 7th gen civic:
Yes, you can rev-match when downshifting. But in technical terms, you only dbl-clutch if you want to d-shift into 1st (why you would do that, I don't know). The car doesn't let you downshift into 1st most often (unless you are going really slow). BUT, you can fool the car. In 2nd, and going slow, press clutch, rev to 3k or so, move shifter into 1st, clutch up. A/K/A rev-matching.
As I said, the car doesn't let you d-shift into first. But if you do this, it will let you shift into 1st gear because the rpms are high enough (as if you were shifting from 1 to 2).
actually, it does. I down shift in to first all the time. Especially when I'm autocrossing, where most tracks are only 1st and 2nd gear.
3. release clutch -> this is the double clutching step. It hooks the engine up to the tranny and spins up the tranny's input shaft.
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Rep Power: 0 the engine is connected to the wheels like this
engine -> clutch -> tranny -> wheels
in slightly more detail, within the tranny, there are three stages
input shaft > gear -> output shaft
the output shaft is connected to the wheels, the input shaft is connected to the clutch.
when you disengage the clutch, the input shaft naturally slows down due to friction as it's no longer connected to the engine. This shaft has to be spinning at the same speed as the engine in order for you to shift into a gear. This is what synchros do, they spin this shaft up to speed whenever you move the shift ****. I have no clue how they work exactly tho.
in rev-matching, the clutch stays down the entire time, disconnecting the engine from the tranny. The input shaft on the tranny slows down as a result. Having synchros however, they spin the shaft back up to speed as you shift and allow you to go into gear.
in dbl-clutching, you release in neutral to connect the engine back to the tranny, spinning the input shaft using the engine rather than the synchros doing that job.
this is probably why dbl-clutching and rev-matching get so easily mixed up by everyone, because our trannys are synchronized, it's not possible to feel the difference between the two, unless you are the driver. the shifter will go into gears smoother if you are actually double clutching, but the process is slower than rev-matching for obvious reasons.
if you want to feel how it's like to shift in an unsynced car, let the car roll backwards and try shift into reverse. I don't REALLY suggest it, but reverse is the one unsynced gear in our trannys, so you'll see how it's like.
engine -> clutch -> tranny -> wheels
in slightly more detail, within the tranny, there are three stages
input shaft > gear -> output shaft
the output shaft is connected to the wheels, the input shaft is connected to the clutch.
when you disengage the clutch, the input shaft naturally slows down due to friction as it's no longer connected to the engine. This shaft has to be spinning at the same speed as the engine in order for you to shift into a gear. This is what synchros do, they spin this shaft up to speed whenever you move the shift ****. I have no clue how they work exactly tho.
in rev-matching, the clutch stays down the entire time, disconnecting the engine from the tranny. The input shaft on the tranny slows down as a result. Having synchros however, they spin the shaft back up to speed as you shift and allow you to go into gear.
in dbl-clutching, you release in neutral to connect the engine back to the tranny, spinning the input shaft using the engine rather than the synchros doing that job.
this is probably why dbl-clutching and rev-matching get so easily mixed up by everyone, because our trannys are synchronized, it's not possible to feel the difference between the two, unless you are the driver. the shifter will go into gears smoother if you are actually double clutching, but the process is slower than rev-matching for obvious reasons.
if you want to feel how it's like to shift in an unsynced car, let the car roll backwards and try shift into reverse. I don't REALLY suggest it, but reverse is the one unsynced gear in our trannys, so you'll see how it's like.
