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      03-21-2011, 01:40 PM   #133
Prince_of_Persia
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Quote:
Originally Posted by elp_jc View Post
First of all, you're assuming that car is not decelerating, which is usually the case. And most importantly, that'd be the rpm at which the clutch should be engaged, meaning engine has to be 'blipped' a bit higher to allow engine rpm to drop to that level while clutch pedal is released . Makes sense? Fun stuff.

By the way, doing this on straight gate downshifts, like 4-3, or 6-5, is easier, but it becomes trickier on cross-gatet downshifts, especially on lower gears, like 3-2, where it feels a lot jerkier if not executed properly. This is why driving a manual never becomes boring . Good day gang.
Yeah I noticed. 3-2 rev-matching is way harder than 4-3.
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      03-21-2011, 02:03 PM   #134
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Quote:
Originally Posted by Prince_of_Persia View Post
Yeah I noticed. 3-2 rev-matching is way harder than 4-3.
Until you perfect the technique, at which time it will become second nature, you are probably better of "overblipping" slightly than "underblipping"/

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      03-22-2011, 12:43 AM   #135
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My 'trick' to rev match (as close as I can) on downshifts is to keep the throttle at the same pressure (ie: don't move my foot on the gas). I take it out of gear, because there's some pressure on the engine (let's say you're accelerating a little or keeping speed) the revs will naturally go up by a bit.

Usually that's just enough rpm increase to rev match on the downshift.

After a while you get the hang of the different deltas between 3rd and 2nd, or 6th and 5th for example. You also get a 'feel' for how much initial pressure is necessary and how much you compensate before downshifting.

I tried lifting off the gas and then trying to rev match, ... impossible for me. Now I just keep my foot on, the revs go up naturally, and usually land where they need to on downshift for a reasonably smooth transition.

If you doubt the necessary rev range, as others suggested, just double declutch to get the synchros happy and slip it in the next lowest gear.
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      03-22-2011, 09:56 AM   #136
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Quote:
Originally Posted by EstorilDan View Post
My 'trick' to rev match (as close as I can) on downshifts is to keep the throttle at the same pressure (ie: don't move my foot on the gas). I take it out of gear, because there's some pressure on the engine (let's say you're accelerating a little or keeping speed) the revs will naturally go up by a bit.

...
I feel like this technique will cause more clutch wear.
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      03-22-2011, 10:22 AM   #137
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      03-22-2011, 07:18 PM   #138
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Quote:
Originally Posted by captainaudio View Post
Downshifting in the middle of a turn is never a good idea as it can cause trailing clutch oversteer (TCO). On a track downshifting and threshold braking is done while the car is going straight. You can prgressively release the brakes (trail brake) as you go around the curve. This technique can be used to mildly rotate the car and help get it pointed in the right direction.

A drift can be initialted by snapping off the accellerator to break the rear tires loose and then applying enough throttle to keep them spinning. By modulating the throttle and the steering a drift can be held throughout the corner. This not really something that is done in track driving as it may look spectacular but is by no means the fastest way to get around a turn.

The best place to practice is on a wet skid pad.
Nicely said.
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      03-23-2011, 08:11 AM   #139
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After practicing for a while, I can do it more than 95% of the time. As you guys suggested here, i practiced more when i had to slow down for a red light or something. It is so fun to get it right !!!
Now going to practice heel and toe.

Thanks a lot for your help
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      03-23-2011, 08:27 AM   #140
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Glad to hear you're enjoying your car. Even after we hijacked your thread.

You'll find heel and toe is very difficult in this car if you aren't fairly hard on the brakes. If you can do it well under light braking, you're doing well.
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      03-23-2011, 09:52 AM   #141
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Quote:
Originally Posted by Prince_of_Persia View Post
After practicing for a while, I can do it more than 95% of the time. As you guys suggested here, i practiced more when i had to slow down for a red light or something. It is so fun to get it right !!!
Now going to practice heel and toe.

Thanks a lot for your help
Congrats.

I spent about 6 months practicing rev matched down shifts before I moved to heel&toe. Be VERY careful.. You may carry more speed than you want through a corner, or you may decelarate fast causing someone rear end you...

Also it helped me a lot to get a short lesson from a PCA instructor when I was at their driver skills event. It is very crucial (at least when you're learning) how you place your heel.
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      03-23-2011, 10:52 AM   #142
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What a fascinating thread. In the absence of learning proper heel/toe'ing (which I'm trying and I WILL learn properly some day) I've been doing the rev match thing ever since I took delivery of the car and besides being fun (and a real treat for the ears), you just know that it's good for the car if done right.
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