Do you rev match downshift (no heel/toe)
04-30-2018, 10:33 AM
#32
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The purpose of downshifting has NOTHING to do with slowing. It has ONLY to do with selecting the optimal gear to apply the best power THROUGH and OFF the turn you’re entering.
I read the a), b), c) progression as mastering three fundamental concepts to allow the best passage from vMax through to the exit of the corner, not that Jabs was advocating bringing the last downshift OR maximal braking PAST the beginning of the trail-brake phase, just UP TO IT. Which is what you want to do, in a perfect world...
04-30-2018, 10:34 AM
#33
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With all due respect, here's evidence that that is NOT the case, if done properly and well.
915 gearbox, 3.0-liter carbureted engine, no ABS, R7 Hoosiers. Listen and weep, or learn...
https://youtu.be/p9qY-SipYtA
915 gearbox, 3.0-liter carbureted engine, no ABS, R7 Hoosiers. Listen and weep, or learn...
https://youtu.be/p9qY-SipYtA
112-115 mph through turn 2, and perfect line through the esses.
I want my video to look and sound like that.
04-30-2018, 10:38 AM
#34
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So do I! 
In this case, he DID need to pause in his acceleration at and just past the direction change into T3 due to the fact that this car has NO wings, splitters, canards or anything other than a small, short ducktail on the engine lid.
He needed to pitch forward to weight the nose and begin the direction change, as the road leveled out and the car unloaded (lost front grip). Once it began the change in direction, he was right back to the quick progression to WOT and got a good exit over the tunnel. A lot of relatively heavy street cars need to do this, especially on treaded tires.
My friend and client, on his way to winning the Masters class in GT4 CS a few years ago, was flat between turn-in for T1 and braking at the Bus Stop. But he worked his way incrementally to doing that.
Same kind of work to do Road Atlanta T12...
I think “flat” is overrated. That’s not where the real improvements in lap time come from, anyway. But it makes for good Seneca Lodge bar talk!
In this case, he DID need to pause in his acceleration at and just past the direction change into T3 due to the fact that this car has NO wings, splitters, canards or anything other than a small, short ducktail on the engine lid.
He needed to pitch forward to weight the nose and begin the direction change, as the road leveled out and the car unloaded (lost front grip). Once it began the change in direction, he was right back to the quick progression to WOT and got a good exit over the tunnel. A lot of relatively heavy street cars need to do this, especially on treaded tires.
My friend and client, on his way to winning the Masters class in GT4 CS a few years ago, was flat between turn-in for T1 and braking at the Bus Stop. But he worked his way incrementally to doing that.
Same kind of work to do Road Atlanta T12...
I think “flat” is overrated. That’s not where the real improvements in lap time come from, anyway. But it makes for good Seneca Lodge bar talk!
04-30-2018, 07:20 PM
#35
Originally Posted by MSR Racer
Learning race car driving is like most other skilled trades...often you got to go to school for it. OP is best served by getting a coach.
04-30-2018, 08:40 PM
#36
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Originally Posted by ProCoach
So do I!
In this case, he DID need to pause in his acceleration at and just past the direction change into T3 due to the fact that this car has NO wings, splitters, canards or anything other than a small, short ducktail on the engine lid.
He needed to pitch forward to weight the nose and begin the direction change, as the road leveled out and the car unloaded (lost front grip). Once it began the change in direction, he was right back to the quick progression to WOT and got a good exit over the tunnel. A lot of relatively heavy street cars need to do this, especially on treaded tires.
My friend and client, on his way to winning the Masters class in GT4 CS a few years ago, was flat between turn-in for T1 and braking at the Bus Stop. But he worked his way incrementally to doing that.
Same kind of work to do Road Atlanta T12...
I think “flat” is overrated. That’s not where the real improvements in lap time come from, anyway. But it makes for good Seneca Lodge bar talk!
In this case, he DID need to pause in his acceleration at and just past the direction change into T3 due to the fact that this car has NO wings, splitters, canards or anything other than a small, short ducktail on the engine lid.
He needed to pitch forward to weight the nose and begin the direction change, as the road leveled out and the car unloaded (lost front grip). Once it began the change in direction, he was right back to the quick progression to WOT and got a good exit over the tunnel. A lot of relatively heavy street cars need to do this, especially on treaded tires.
My friend and client, on his way to winning the Masters class in GT4 CS a few years ago, was flat between turn-in for T1 and braking at the Bus Stop. But he worked his way incrementally to doing that.
Same kind of work to do Road Atlanta T12...
I think “flat” is overrated. That’s not where the real improvements in lap time come from, anyway. But it makes for good Seneca Lodge bar talk!
Last edited by Veloce Raptor; 05-01-2018 at 09:37 AM.
04-30-2018, 08:49 PM
#37
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You've been there. You know.
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05-01-2018, 07:53 AM
#38
Still not sure about the answer to my question....
Option A: Brakes on. Clutch down. Shift to 3rd. Clutch up. Brakes off. Turn in.
Option B: Brakes on. Clutch down. Shift to 3rd. Brakes off to blip throttle for rev match. Clutch up. Turn in. (This entails releasing the brake earlier, and reducing braking time)
- You're driving down the straight at 100+
- You're in 4th gear, and need to shift down to 3rd.
- You do not yet know how to heel/toe, and you will not be learning it in the next 2 seconds, either.
Option A: Brakes on. Clutch down. Shift to 3rd. Clutch up. Brakes off. Turn in.
Option B: Brakes on. Clutch down. Shift to 3rd. Brakes off to blip throttle for rev match. Clutch up. Turn in. (This entails releasing the brake earlier, and reducing braking time)
05-01-2018, 08:00 AM
#39
Rennlist Member
At this level of development where this question is of genuine interest just release the clutch pedal slowly to avoid locking the drive wheels and let the synchro do its job.
So I guess A.
So I guess A.
05-01-2018, 09:52 AM
#40
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Originally Posted by ProCoach
You've been there. You know.
Deed
05-01-2018, 02:04 PM
#41
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Still not sure about the answer to my question....
Option A: Brakes on. Clutch down. Shift to 3rd. Clutch up. Brakes off. Turn in.
Option B: Brakes on. Clutch down. Shift to 3rd. Brakes off to blip throttle for rev match. Clutch up. Turn in. (This entails releasing the brake earlier, and reducing braking time)
- You're driving down the straight at 100+
- You're in 4th gear, and need to shift down to 3rd.
- You do not yet know how to heel/toe, and you will not be learning it in the next 2 seconds, either.
Option A: Brakes on. Clutch down. Shift to 3rd. Clutch up. Brakes off. Turn in.
Option B: Brakes on. Clutch down. Shift to 3rd. Brakes off to blip throttle for rev match. Clutch up. Turn in. (This entails releasing the brake earlier, and reducing braking time)
For early DE, the answer is simple: brake in a straight line, then shift, then turn (option A, without overlapping brake and clutch)...
To advance without heal toe the end result (blending inputs) is the same. You can still blend braking-turning but when you shift you now have to blend in pulling up the engine RPM. Knowing the last step takes some traction, you will need to bleed off the brakes even more. It will be a delicate balancing act of bleeding off the brakes as you slowly let the clutch out, then squeezing back on as the motor starts to come up to speed.. I'm not sure I could do it effectively.
Last edited by jscott82; 05-01-2018 at 02:20 PM.
05-01-2018, 02:55 PM
#42
With all due respect, here's evidence that that is NOT the case, if done properly and well.
915 gearbox, 3.0-liter carbureted engine, no ABS, R7 Hoosiers. Listen and weep, or learn...
https://youtu.be/p9qY-SipYtA
915 gearbox, 3.0-liter carbureted engine, no ABS, R7 Hoosiers. Listen and weep, or learn...
https://youtu.be/p9qY-SipYtA
BTW, Why didn't the guy in the video run A-7's, he'd go faster
05-01-2018, 03:47 PM
#43
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Not even close to a modern car. Not even close to PCA GT4 spec... With a PDK-equipped Cayman, you wouldn't get the chance to master this vanishing technique!
Besides, I hear no lockup, no see-saw effect from inconsistent brake pressure. It can be done, and done well.These old cars move around underneath you, they require lots of concentration, they're fun. And they race against other old cars, not modern cars. At this level of driving, the difference would be minimal between A7's and R7's, anyway. That's why it's great that there's a choice.
This video demonstrates proper technique in timing, throttle, clutch release and power application. Proper brake technique without the ABS safety blanket, too. That's why it's posted here.
05-01-2018, 04:01 PM
#44
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Still not sure about the answer to my question....
Option A: Brakes on. Clutch down. Shift to 3rd. Clutch up. Brakes off. Turn in.
Option B: Brakes on. Clutch down. Shift to 3rd. Brakes off to blip throttle for rev match. Clutch up. Turn in. (This entails releasing the brake earlier, and reducing braking time)
- You're driving down the straight at 100+
- You're in 4th gear, and need to shift down to 3rd.
- You do not yet know how to heel/toe, and you will not be learning it in the next 2 seconds, either.
Option A: Brakes on. Clutch down. Shift to 3rd. Clutch up. Brakes off. Turn in.
Option B: Brakes on. Clutch down. Shift to 3rd. Brakes off to blip throttle for rev match. Clutch up. Turn in. (This entails releasing the brake earlier, and reducing braking time)
05-01-2018, 04:06 PM
#45
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I'll just add the caveat that for most who select Option A, DO NOT DALLY in releasing the clutch.
If the downshift occurs too early (car going too fast for the lower gear), or the clutch is depressed long enough to "lose" the rpm's, then the deleterious effect of the clutch release is magnified.
If the downshift occurs too early (car going too fast for the lower gear), or the clutch is depressed long enough to "lose" the rpm's, then the deleterious effect of the clutch release is magnified.