Do you rev match downshift (no heel/toe)
04-29-2018, 06:41 PM
#16
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you can get away with it, but it is a finesse move and it requires a slightly earlier braking point. sometimes it can be beneficial to give a real quick breath to the brakes between a single shift, but multiple shifts, its better to heal toe. most important is the rev matching though! (that should be priority if the pedals are not configured correctly, or you have physical issues)
04-29-2018, 07:10 PM
#17
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Most folks blip way too big, and way too early, too.
Stabs or roll of the ankle to hit the side of the shoe works, too. Rarely do I see people using only the sole of the shoe.
04-29-2018, 09:46 PM
#18
Like I said, for various reasons, I will not be doing heel/toe.
No pedal extensions in my future. I just casually enjoy 1 track day a year.
Would you rev match at the end of a straight, or is that a bad idea?
No pedal extensions in my future. I just casually enjoy 1 track day a year.
Would you rev match at the end of a straight, or is that a bad idea?
04-29-2018, 09:57 PM
#19
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I don't understand.
How much speed do you need to get off at the end of "a straight?"
It's more important to get the speed off in an efficient way, using the brakes, than to try and rely on engine braking to slow the car in a consistent, quick and efficient way.
If you can't or won't integrate the (multiple) downshifts with the slowing (in this case, braking), then focus on the slowing and downshift ONE TIME at the end of slowing, just before the minimum speed at the entry of the corner.
This way, the lack of rev matching (or only rev matching for the single downshift preceding the corner entry) will have a minimal detrimental effect to chassis balance, time or car attitude AT the entry to the corner.
How much speed do you need to get off at the end of "a straight?"
It's more important to get the speed off in an efficient way, using the brakes, than to try and rely on engine braking to slow the car in a consistent, quick and efficient way.
If you can't or won't integrate the (multiple) downshifts with the slowing (in this case, braking), then focus on the slowing and downshift ONE TIME at the end of slowing, just before the minimum speed at the entry of the corner.
This way, the lack of rev matching (or only rev matching for the single downshift preceding the corner entry) will have a minimal detrimental effect to chassis balance, time or car attitude AT the entry to the corner.
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Consultation Available Remotely and at VIRginia International Raceway
04-29-2018, 10:02 PM
#20
Registered User
Timely thread... not sure why, but I find heel toe blipping on the track, when you are trying to go quick, really difficult and time consuming... on the street, no problem...
braking from high high speed before a corner, and downshifting sequentially 4-3-2 while blipping really slows progress, at least for me... dang near impossible to just blip 1000-2000 rpm. Usually way over shoots or under shoots.. at least with the 930. What's the secret here?
is blipping any any worse than just rev matching? When downshifting, right foot hits the brake, clutch goes in, downshift while heel presses gas pedal a quarter inch or so, and shift...
when you you guys are downshifting 4-3-2, and heel toe blipping, the clutch is pressed to the floor the whole time? Do you lift off a bit to get the internals up to speed between gears? Double clutch?
so basically i think I do rev matching, rather than blipping... is that worse? Car seems fine, doesn't get unsettled...
of interst, just started tracking a BMW z3 1.9. Car needs a lot of work, it's squirrely... but, downshifting even without rev matching is smooth as silk... that little motor poses almost no resistance to rotation...
braking from high high speed before a corner, and downshifting sequentially 4-3-2 while blipping really slows progress, at least for me... dang near impossible to just blip 1000-2000 rpm. Usually way over shoots or under shoots.. at least with the 930. What's the secret here?
is blipping any any worse than just rev matching? When downshifting, right foot hits the brake, clutch goes in, downshift while heel presses gas pedal a quarter inch or so, and shift...
when you you guys are downshifting 4-3-2, and heel toe blipping, the clutch is pressed to the floor the whole time? Do you lift off a bit to get the internals up to speed between gears? Double clutch?
so basically i think I do rev matching, rather than blipping... is that worse? Car seems fine, doesn't get unsettled...
of interst, just started tracking a BMW z3 1.9. Car needs a lot of work, it's squirrely... but, downshifting even without rev matching is smooth as silk... that little motor poses almost no resistance to rotation...
04-29-2018, 10:19 PM
#22
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I guess I'm still confused.
The purpose of heel and toe downshifting is to MATCH THE REVS of the engine TO VEHICLE SPEED upon release of the clutch.
This is done to prevent having the revs drop so precipitously that the rear wheel speeds are HIGHER than what the engine revs WOULD be if not blipped, brought up or otherwise "rev matched."
The best downshifts I've heard have NO OVERSHOOT (revs going MUCH higher with clutch disengaged than when released) or UNDERSHOOT (chirping the rear wheels when the revs drop so much) that the engine is brought back up to speed when the clutch is released.
The goal IS to "rev match" perfectly upon release of the clutch IN THE LOWER GEAR. This allows a seamless slowing and minimal change in the dynamic platform of the chassis.
The best downshifts I've heard COMBINE the slowing of the car at the same rate as if the downshifts were NOT occuring, by effective and efficient and maximal braking BUT INCLUDING the perfect timing of rev matching, downshifting and release of the clutch in the lower gear.
When I was young and dumb, I spent a lot of time working on seamlessly matching revs as I slowed and downshifted. Not too much, not too little. Problem was, when I was on track, I wasn't slowing quickly enough this way because I hadn't integrated the proper use of the brakes in all of this! So, my early instructors and coaches helped me to prioritize braking, THEN integrate the downshifts, with precise rev matching before clutch release, WHILE MAINTAINING EVEN BRAKE PRESSURE THROUGHOUT.
In order to do this well, you need to learn WHAT the gear spacing is, practice the timing, take into account the flywheel effect of your car (heavy allows for more time to do this, light means you are more likely to "lose the revs" if you dawdle) and practice, practice, practice.
What am I missing?
The purpose of heel and toe downshifting is to MATCH THE REVS of the engine TO VEHICLE SPEED upon release of the clutch.
This is done to prevent having the revs drop so precipitously that the rear wheel speeds are HIGHER than what the engine revs WOULD be if not blipped, brought up or otherwise "rev matched."
The best downshifts I've heard have NO OVERSHOOT (revs going MUCH higher with clutch disengaged than when released) or UNDERSHOOT (chirping the rear wheels when the revs drop so much) that the engine is brought back up to speed when the clutch is released.
The goal IS to "rev match" perfectly upon release of the clutch IN THE LOWER GEAR. This allows a seamless slowing and minimal change in the dynamic platform of the chassis.
The best downshifts I've heard COMBINE the slowing of the car at the same rate as if the downshifts were NOT occuring, by effective and efficient and maximal braking BUT INCLUDING the perfect timing of rev matching, downshifting and release of the clutch in the lower gear.
When I was young and dumb, I spent a lot of time working on seamlessly matching revs as I slowed and downshifted. Not too much, not too little. Problem was, when I was on track, I wasn't slowing quickly enough this way because I hadn't integrated the proper use of the brakes in all of this! So, my early instructors and coaches helped me to prioritize braking, THEN integrate the downshifts, with precise rev matching before clutch release, WHILE MAINTAINING EVEN BRAKE PRESSURE THROUGHOUT.
In order to do this well, you need to learn WHAT the gear spacing is, practice the timing, take into account the flywheel effect of your car (heavy allows for more time to do this, light means you are more likely to "lose the revs" if you dawdle) and practice, practice, practice.
What am I missing?
04-29-2018, 10:25 PM
#23
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Timely thread... not sure why, but I find heel toe blipping on the track, when you are trying to go quick, really difficult and time consuming... on the street, no problem...
braking from high high speed before a corner, and downshifting sequentially 4-3-2 while blipping really slows progress, at least for me...
Do you lift off a bit to get the internals up to speed between gears? Double clutch?
braking from high high speed before a corner, and downshifting sequentially 4-3-2 while blipping really slows progress, at least for me...
Do you lift off a bit to get the internals up to speed between gears? Double clutch?
We used to teach "double declutching" at Skip Barber many decades ago.
This was: 1) brake, 2) depress the clutch (dip it), 3) blip the throttle, 4) select neutral, 5) release the clutch, 6) depress the clutch (dip it), blip the throttle, 7) select the lower gear, 8) release the clutch as the trevs drop to the proper speed. Rinse, lather, repeat...
But it really isn't necessary to release the clutch BETWEEN downshifts to allow the transmission shafts to come back up to speed, unless you have a very dead synchro, IMO.
Just make sure the engine revs aren't singificantly above or below the speed that matches the rear wheels in the lower gears awhen you finally release the clutch...
In the non-syncro Hewland racing gearboxes, once the car is moving, I don't even use the clutch going up OR coming down. Really nice!
04-29-2018, 10:59 PM
#24
Timely thread... not sure why, but I find heel toe blipping on the track, when you are trying to go quick, really difficult and time consuming... on the street, no problem...
braking from high high speed before a corner, and downshifting sequentially 4-3-2 while blipping really slows progress, at least for me... dang near impossible to just blip 1000-2000 rpm. Usually way over shoots or under shoots.. at least with the 930. What's the secret here?
is blipping any any worse than just rev matching? When downshifting, right foot hits the brake, clutch goes in, downshift while heel presses gas pedal a quarter inch or so, and shift...
when you you guys are downshifting 4-3-2, and heel toe blipping, the clutch is pressed to the floor the whole time? Do you lift off a bit to get the internals up to speed between gears? Double clutch?
so basically i think I do rev matching, rather than blipping... is that worse? Car seems fine, doesn't get unsettled...
of interst, just started tracking a BMW z3 1.9. Car needs a lot of work, it's squirrely... but, downshifting even without rev matching is smooth as silk... that little motor poses almost no resistance to rotation...
braking from high high speed before a corner, and downshifting sequentially 4-3-2 while blipping really slows progress, at least for me... dang near impossible to just blip 1000-2000 rpm. Usually way over shoots or under shoots.. at least with the 930. What's the secret here?
is blipping any any worse than just rev matching? When downshifting, right foot hits the brake, clutch goes in, downshift while heel presses gas pedal a quarter inch or so, and shift...
when you you guys are downshifting 4-3-2, and heel toe blipping, the clutch is pressed to the floor the whole time? Do you lift off a bit to get the internals up to speed between gears? Double clutch?
so basically i think I do rev matching, rather than blipping... is that worse? Car seems fine, doesn't get unsettled...
of interst, just started tracking a BMW z3 1.9. Car needs a lot of work, it's squirrely... but, downshifting even without rev matching is smooth as silk... that little motor poses almost no resistance to rotation...
04-29-2018, 11:46 PM
#25
Now, one thing I did do is I mimicked the pedal setup of the M3 in my driving simulator including the floor hinged gas pedal and using a load block for the brake (so that it responded to pressure). I modified the pedals that came with my Logitech G25. I used that setup to practice heel-toe whenever I was simracing and I think it helped.
The rev matches don't have to be all that high if you are patient to wait for the end of the braking zone or to space out multiple downshifts during the braking zone. Timing of the blips is more important than the magnitude of the blips.
-Mike
04-30-2018, 12:28 AM
#26
With all due respect:
This thread needs to have a 915 tranny caveat.
It also needs a NO ABS caveat too. Constant pressure just gets you flat spots. My size 13 braking foot pulses like a mad man when hauling down my G bodied car with race slicks.
Today's modern car gives more forgiveness than you can get from a priest in confession
This thread needs to have a 915 tranny caveat.
It also needs a NO ABS caveat too. Constant pressure just gets you flat spots. My size 13 braking foot pulses like a mad man when hauling down my G bodied car with race slicks.
Today's modern car gives more forgiveness than you can get from a priest in confession
04-30-2018, 08:05 AM
#27
Rennlist Member
How about a different approach? Let's discuss the goal and how we prepare you for it.
You are going very fast down a long straight and approaching your brake point. Let's say at this moment you are going 130 mph in 5th gear. Now the question is, what gear do I need to be in when I exit the corner? For this example let's assume you take the corner at 50 mph and your best gear to exit and accelerate out is third. So as you brake and slow down the car you will want to be in third by the time you get through the corner and back onto the throttle. Heel-toe is the method you use to make sure THE CAR REMAINS PERFECTLY BALANCED AT ALL TIMES while performing the downshift. At this point you are dealing with two dimensions, braking (longitudinal) and turning (lateral). Screw one of those up while your tires are screaming at you and bad things are likely to happen.
Ok, you've heard this before... so what? When you begin your track education you are taught to brake hard, then downshift, then turn, go through the corner, and then accelerate at track-out. But as you get better you will start to brake later, and later, and eventually trail that brake all the way into the corner. When you get really good you will trail brake into the corner at high speed, induce a little trail brake oversteer, rotate the car, and be back on throttle BEFORE you reach the apex (on a good day in a proper corner).
What your instructors are teaching you are the basic foundation principles to prepare you for more advanced driving. This started with the whole concept of threshold braking (which includes cars with no ABS) and then moves into heel-toe rev matching (throttle blip is a method of rev matching). So to get really fast into corners you must; a) master threshold braking, then as you get better b) master heel-toe downshifting, then as you get better c) master trail braking (which brings both of those concepts into your turn in point), and eventually d) you will be trail braking deep into the corner thus maintaining mid-corner speed and getting back on the throttle earlier.
Sorry for the long post but it seemed like a few of the readers needed some context to understand why you even care about this funky ankle twisting maneuver your instructors insist you master.
You are going very fast down a long straight and approaching your brake point. Let's say at this moment you are going 130 mph in 5th gear. Now the question is, what gear do I need to be in when I exit the corner? For this example let's assume you take the corner at 50 mph and your best gear to exit and accelerate out is third. So as you brake and slow down the car you will want to be in third by the time you get through the corner and back onto the throttle. Heel-toe is the method you use to make sure THE CAR REMAINS PERFECTLY BALANCED AT ALL TIMES while performing the downshift. At this point you are dealing with two dimensions, braking (longitudinal) and turning (lateral). Screw one of those up while your tires are screaming at you and bad things are likely to happen.
Ok, you've heard this before... so what? When you begin your track education you are taught to brake hard, then downshift, then turn, go through the corner, and then accelerate at track-out. But as you get better you will start to brake later, and later, and eventually trail that brake all the way into the corner. When you get really good you will trail brake into the corner at high speed, induce a little trail brake oversteer, rotate the car, and be back on throttle BEFORE you reach the apex (on a good day in a proper corner).
What your instructors are teaching you are the basic foundation principles to prepare you for more advanced driving. This started with the whole concept of threshold braking (which includes cars with no ABS) and then moves into heel-toe rev matching (throttle blip is a method of rev matching). So to get really fast into corners you must; a) master threshold braking, then as you get better b) master heel-toe downshifting, then as you get better c) master trail braking (which brings both of those concepts into your turn in point), and eventually d) you will be trail braking deep into the corner thus maintaining mid-corner speed and getting back on the throttle earlier.
Sorry for the long post but it seemed like a few of the readers needed some context to understand why you even care about this funky ankle twisting maneuver your instructors insist you master.
04-30-2018, 08:11 AM
#28
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915 gearbox, 3.0-liter carbureted engine, no ABS, R7 Hoosiers. Listen and weep, or learn...
04-30-2018, 08:18 AM
#29
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Originally Posted by ProCoach
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...
915 gearbox, 3.0-liter carbureted engine, no ABS, R7 Hoosiers. Listen and weep, or learn...
04-30-2018, 10:09 AM
#30
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How about a different approach? Let's discuss the goal and how we prepare you for it.
You are going very fast down a long straight and approaching your brake point. Let's say at this moment you are going 130 mph in 5th gear. Now the question is, what gear do I need to be in when I exit the corner? For this example let's assume you take the corner at 50 mph and your best gear to exit and accelerate out is third. So as you brake and slow down the car you will want to be in third by the time you get through the corner and back onto the throttle. Heel-toe is the method you use to make sure THE CAR REMAINS PERFECTLY BALANCED AT ALL TIMES while performing the downshift. At this point you are dealing with two dimensions, braking (longitudinal) and turning (lateral). Screw one of those up while your tires are screaming at you and bad things are likely to happen.
Ok, you've heard this before... so what? When you begin your track education you are taught to brake hard, then downshift, then turn, go through the corner, and then accelerate at track-out. But as you get better you will start to brake later, and later, and eventually trail that brake all the way into the corner. When you get really good you will trail brake into the corner at high speed, induce a little trail brake oversteer, rotate the car, and be back on throttle BEFORE you reach the apex (on a good day in a proper corner).
What your instructors are teaching you are the basic foundation principles to prepare you for more advanced driving. This started with the whole concept of threshold braking (which includes cars with no ABS) and then moves into heel-toe rev matching (throttle blip is a method of rev matching). So to get really fast into corners you must; a) master threshold braking, then as you get better b) master heel-toe downshifting, then as you get better c) master trail braking (which brings both of those concepts into your turn in point), and eventually d) you will be trail braking deep into the corner thus maintaining mid-corner speed and getting back on the throttle earlier.
Sorry for the long post but it seemed like a few of the readers needed some context to understand why you even care about this funky ankle twisting maneuver your instructors insist you master.
You are going very fast down a long straight and approaching your brake point. Let's say at this moment you are going 130 mph in 5th gear. Now the question is, what gear do I need to be in when I exit the corner? For this example let's assume you take the corner at 50 mph and your best gear to exit and accelerate out is third. So as you brake and slow down the car you will want to be in third by the time you get through the corner and back onto the throttle. Heel-toe is the method you use to make sure THE CAR REMAINS PERFECTLY BALANCED AT ALL TIMES while performing the downshift. At this point you are dealing with two dimensions, braking (longitudinal) and turning (lateral). Screw one of those up while your tires are screaming at you and bad things are likely to happen.
Ok, you've heard this before... so what? When you begin your track education you are taught to brake hard, then downshift, then turn, go through the corner, and then accelerate at track-out. But as you get better you will start to brake later, and later, and eventually trail that brake all the way into the corner. When you get really good you will trail brake into the corner at high speed, induce a little trail brake oversteer, rotate the car, and be back on throttle BEFORE you reach the apex (on a good day in a proper corner).
What your instructors are teaching you are the basic foundation principles to prepare you for more advanced driving. This started with the whole concept of threshold braking (which includes cars with no ABS) and then moves into heel-toe rev matching (throttle blip is a method of rev matching). So to get really fast into corners you must; a) master threshold braking, then as you get better b) master heel-toe downshifting, then as you get better c) master trail braking (which brings both of those concepts into your turn in point), and eventually d) you will be trail braking deep into the corner thus maintaining mid-corner speed and getting back on the throttle earlier.
Sorry for the long post but it seemed like a few of the readers needed some context to understand why you even care about this funky ankle twisting maneuver your instructors insist you master.