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      11-13-2015, 07:17 AM   #23
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Pure speculation but could the throttle stabs be a method to find the balance between oversteer and understeer into and out of the corner? Did Senna use this technique in low- torque high-revving cars mostly?
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      11-13-2015, 07:45 AM   #24
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Quote:
Originally Posted by pgviper View Post
What is the point of left foot braking? Never really got a clear answer.
On a go kart throttle = right foot brake = left foot...
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Last edited by bueller; 11-13-2015 at 07:52 AM..
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      11-13-2015, 08:37 AM   #25
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Quote:
Originally Posted by wdb View Post
Love the Senna vid. Pobst was tolerable in that vid but he still tries too hard. Neither of them was double-clutching; maybe that makes me a throwback...
No need to double clutch unless you're in a semi these days.
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      11-13-2015, 11:54 AM   #26
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Quote:
Originally Posted by Alfisti View Post
Yeah senna prods the gas a lot mid corner, trying to provoke the ass end maybe? He was freaking busy.
I used to see this a lot with the Japanese drivers in old Options videos
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      11-13-2015, 12:13 PM   #27
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He says to rev match you depress the clutch, then downshift while blipping the throttle, then let go of the clutch. I never blip the throttle while the clutch is depressed. That seems like a good way to wear out your clutch. Instead, I shift into neutral then blip the throttle, then down shift, then let off the clutch while I'm pressing the throttle again. Which way do you guys rev match?
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      11-13-2015, 02:20 PM   #28
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Quote:
Originally Posted by Twixboy View Post
He says to rev match you depress the clutch, then downshift while blipping the throttle, then let go of the clutch. I never blip the throttle while the clutch is depressed. That seems like a good way to wear out your clutch. Instead, I shift into neutral then blip the throttle, then down shift, then let off the clutch while I'm pressing the throttle again. Which way do you guys rev match?
If you blip the throttle while depressing the clutch the engine revs free'er since the transmission side is not bogging the engine with weight. You want to time it so as you engage the lower gear (while in your heel & toe downshift ) the revs are cascading down. Remember: work on the theory that each downshift will require a 1000rpm blip over the rpm you were maintaining at the gear you just evacuated.

I'm having a little trouble following twixboy example since there is no reference to braking - but don't worry about applying throttle with clutch pedal depressed.
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      11-13-2015, 02:57 PM   #29
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Quote:
Originally Posted by Twixboy View Post
He says to rev match you depress the clutch, then downshift while blipping the throttle, then let go of the clutch. I never blip the throttle while the clutch is depressed. That seems like a good way to wear out your clutch. Instead, I shift into neutral then blip the throttle, then down shift, then let off the clutch while I'm pressing the throttle again. Which way do you guys rev match?
What you're talking about is a double-clutch rev match downshift. The only real benefit to this is that by releasing the clutch in neutral and then blipping the throttle, you're bringing the intermediate shaft to the same speed as the engine, so the syncros have little work to do and you can slide into gear easily. Very smooth and low wear, but slower.

As shown in the video, a rev match downshift only requires a single press of the clutch, but requires the syncros to match a larger speed differential.
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      11-13-2015, 03:05 PM   #30
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Quote:
Originally Posted by RJ_ View Post
What you're talking about is a double-clutch rev match downshift. The only real benefit to this is that by releasing the clutch in neutral and then blipping the throttle, you're bringing the intermediate shaft to the same speed as the engine, so the syncros have little work to do and you can slide into gear easily. Very smooth and low wear, but slower.

As shown in the video, a rev match downshift only requires a single press of the clutch, but requires the syncros to match a larger speed differential.
Thanks, I think the big difference here is that the video is talking about heel & toe for quick downshifts at the track, whereas I'm talking about rev matching to downshift for regular street driving, e.g. down shifting 1 gear to make a right turn.

I've always been taught to do the double clutch downshift to save my clutch and brakes. Other people say it makes no difference on modern gearboxes and I can just depress the clutch once to downshift, then let the engine do the braking for me as I enter my right turn. For daily driving is there a need to double clutch downshift to prevent damaging my synchros? I have an 2004 Z4 btw, so not as modern as your cars.

Last edited by Twixboy; 11-13-2015 at 03:13 PM..
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      11-13-2015, 03:17 PM   #31
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Quote:
Originally Posted by Twixboy View Post
Thanks, I think the big difference here is that the video is talking about heel & toe for quick shifts at the track, whereas I'm talking about rev matching for regular street driving, e.g. down shifting 1 gear to make a right turn. Do you guys routinely blip the throttle while the clutch is depressed when you're driving on the street?
*To your previous post: Revving the engine with the clutch depressed does not wear your clutch whatsoever. The throwout bearing would take any wear, and it is designed to do exactly that.

Yes. I rev match every downshift to make a turn.

See upcoming turn.
Clutch in
Shift gear
Throttle up to rpm
Clutch out/feather throttle to match
Close throttle
Brake (engine and pedal)
Turn
Open throttle out of corner

Quote:
I've always been taught to do the double clutch downshift to save my clutch and brakes. Other people say it makes no difference on modern gearboxes and I can just depress the clutch once to downshift, then let the engine do the braking for me
Compared to what I mentioned above, the only advantage to double clutching would be that the syncros don't have to work as hard. But shifting hard and fast will wear them much more in the long run than the small savings of double clutching.

However, assuming you don't blip the throttle, the bold part will wear your clutch as it "pulls" the engine speed up to match the vehicle speed. It can also shock the drivetrain if you pop the clutch out too quickly. (Like shown in the video when he spins out.)

Last edited by RJ_; 11-13-2015 at 03:26 PM..
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      11-13-2015, 03:20 PM   #32
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Quote:
Originally Posted by Twixboy View Post
Thanks, I think the big difference here is that the video is talking about heel & toe for quick downshifts at the track, whereas I'm talking about rev matching to downshift for regular street driving, e.g. down shifting 1 gear to make a right turn.

I've always been taught to do the double clutch downshift to save my clutch and brakes. Other people say it makes no difference on modern gearboxes and I can just depress the clutch once to downshift, then let the engine do the braking for me as I enter my right turn. For daily driving is there a need to double clutch downshift to prevent damaging my synchros? I have an 2004 Z4 btw, so not as modern as your cars.
I think you equate double-clutching with rev-matching but they are two different things. To drive smoothly you should almost always rev match especially in lower gears. There is no other way.
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      11-13-2015, 03:29 PM   #33
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Quote:
Originally Posted by Fundguy1 View Post
No need to double clutch unless you're in a semi these days.
It's such a habit I do it without thinking when downshifting most of the time. If I'm hurrying I'll skip the double dip.

I double clutch upshifts when the gearbox is cold. My Zed does not like to shift when its cold.
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      11-14-2015, 01:18 PM   #34
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Quote:
Originally Posted by pgviper View Post
What is the point of left foot braking? Never really got a clear answer.
Quote:
Originally Posted by carzaddict View Post
basically decreasing the time it takes to get off the gas and onto the brake.
It's most effective during trail braking so that you can ease off the brakes and smoothly apply throttle at the same time to balance the car.
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      11-26-2015, 11:05 AM   #35
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Not sure if any of you have driven a RHD manual, but I found it to be a bitch. Took a lot of getting used to.
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      11-26-2015, 10:29 PM   #36
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This video makes me want an ATS-V. Coupe form.

Ehh, still rather have a CTS-V coupe. But the ATS-V is pretty sweet.
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      11-27-2015, 09:13 AM   #37
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Quote:
Originally Posted by BombaE90 View Post
Not sure if any of you have driven a RHD manual, but I found it to be a bitch. Took a lot of getting used to.
I have, and I agree. I kept pulling the shifter in the wrong direction left-to-right; 1st instead of 3rd, that kind of thing. I wanted the shift pattern to be a mirror image. I'd wager that the Brits share our struggles...
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