whats it mean to double clutch and how do u do it?
thanks
dru

 

Its in the faq section here.

 

There should be other threads about this, but here goes:

Keep in mind it's 2am, so forgive me if I blabber.

For upshifting...

Let's say you're in 2nd, and you're doing about 45, and you want to upshift to 3rd. When you upshift straight from 2nd to 3rd, your RPMs drop, and you won't be in the car's (or S2000's) ideal powerband for maximum torque & horsepower.

So, after shifting from 2nd to 3rd, your RPMs would drop to, for example, 3000-4000 RPMs, whereas the ideal would be above 6000 RPMs...so for those few split seconds where your car is below the sweet spot of 6000+ RPMs, your car will "lag" until it hits the ideal powerband.

So, to double clutch...

While in 2nd, depress the clutch to move out of 2nd...

Rev the engine (while in "neutral" to the sweet spot powerband you want...say...for example 6500 RPMs...)

And then depress the clutch again and move into 3rd...

Hence, 'clutching twice' or double clutching...

Note: While downshifting, especially at higher speeds, the engine will automatically rev higher...for example...doing 45 in second, and dropping down to first...

Finally, while this all seems complicated and long...it takes split seconds to do once you get the hang of it.

Hope that helped

 

[QUOTE]Originally posted by xfactor834
[B]There should be other threads about this, but here goes:

Keep in mind it's 2am, so forgive me if I blabber.

For upshifting...

Let's say you're in 2nd, and you're doing about 45, and you want to upshift to 3rd.

 

By the way, there's no such thing as a stupid question here on the board.

 

Man.. toe/heeling is hard!!! How do you guys do it? Heres how I do it, tell me if I'm doing something wrong, cuz I always tend to lurch the car when I let go of the clutch after downshifting.

1. brake
2. clutch+brake, then hit accelerator with heel, downshift
3. let clutch/brake go.

When I do this, the car lurches. Is it supposed to be a smooth transition or do you guys do this too? I should take some driving classes. I wasnt really into this kind of thing, mainly drag racing. But after watch the Best Motoring video, I really wanna learn. Thanks!

 

I suggest you practice this way .... remember safety first

when you approach a stop sign or a red light, put the gear in neutral and let the clutch up, put your toe on the brake, and the heel on gas, it should be the right rear edge of your foot on the gas pedal ; practice feathering / hold the gas pedal at the rpm you'd like while maintaining a consistent braking pressure on the brake pedal. I find this less damaging to your clutch and the drive train. When you are comfortable doing this part, then you can start by adding the clutch and shifting action together.

To learn the gear ratio, the best way is to get familiar with the car's RPM range / difference by double clutching. So when you drop from 6th to 5th, there shouldn't be movements or very minor movements in the car. This can help you get a better sense of how much gas to applied when downshifting to match the speed.

And double clutching would be adding gas before engaging the gear, some does it while the clutch is down, some does it while the clutch is up, personal preferences, whichever way helps and feels good to you. You'd feel the engagement MUCH smoother without the clunks or that notchy feel.

Just my own experiences. Have fun practicing.

 

as mtsw states - practice! and practice at low speeds, or no speed at all - just think about it, work on it, and worry about speed later. smoothness is much more important.

 

First of all the article referenced by Schatten is what you should read. Double clutch downshifting is really cool sounding when coming up to a corner, and is a great way to preserve your synchros (if done properly).

I wouldn't recommend using the next comment about upshifting though. The only practical value I have found for double clutch upshifting is when your primary shaft doesn't wind DOWN quickly enough between shifts. I understand this is a problem with Shelby's new car, and I have noticed it sometimes when my S is cold. The technique is (say 2nd to 3rd) to release the throttle and depress the clutch as usual, push the shifter to neutral, and release the clutch (no throttle blip). Then depress the clutch, shift to third, and depress the throttle while releasing the clutch. Notice that the only difference between a regular shift and this is the clutch is cycled out and in while the tranny is in neutral. This forces the primary shaft to slow down with the engine. The reason it is generally of little value is, if you just delay engaging 3rd from neutral by about the additional time required to do the double clutch in neutral, the transmission would be ready to shift to 3rd anyway.

Practice the downshift though. It's fun.

 

Wait, back to double clutching. What is the point of depressing the clutch twice? When downshifting (let's say from 3rd to 2nd) why wouldn't you depress the clutch, shift from 3rd to 2nd, rev match and then release the clutch?