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Rev-matching while downshifting....

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Old 07-13-2008 | 12:06 PM
  #26  
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Funny. Because I don't see why you all are separating Heel-toing and Double clutching. They are to be used at the same time. If you are double clutching and then braking for the turn you are not gonna be fast. The two techniques are not to be separated. You use the double clutch while you are heel-toing to consolidate your braking distance and your shifting distance before the turn. But I guess I do see how we can just double clutch while on the street during easy driving. But if you wanna learn how to go faster which should be the basis for this thread then one must learn what these techniques are truely for. There is a lot of confusion being dealt out here. The reason I beat half the super cars I race against is purely because these asses who buy supercars don't even know how to drive. By learning the simple Heel-Toe (which includes the use of double clutch) technique you can out brake most possers on the street. It is braking and corner prep that this technique is for. Go download or buy a book on basic high performance driving and instantly wow your friends and destroy Doctors and the like on the street.
Old 07-13-2008 | 12:53 PM
  #27  
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Originally Posted by zero5
... I don't see why you all are separating Heel-toing and Double clutching. They are to be used at the same time...
There are lots of times when you downshift without being on the brakes. Back before disc brakes, racers used to slow down on compression, not brakes. Heel-toe is the answer to the question "How the hell do I do that when I'm on the brakes?"

Jack Brabham, who did come from the disc brake, heel-toe era, said that he never heel-toed when driving on the street. He said that it was associated with a level of violence that wasn't appropriate off the track.

I suspect we have a different concept of violence than Sir Jack.

Originally Posted by zero5
... Go download or buy a book on basic high performance driving and instantly wow your friends ...
Piero Taruffi's book, "The Technique of Motor Racing," is excellent. It's definitely dated for racing, but it's great for the fundamentals if you just want to know what you're doing on the street. Best "how-to" on double clutching and heel-toe that I've seen.

I've seen newer books that pooh-pooh the whole idea of double clutching. They say to just shove it in, let the synchros do the work. I presume those authors were not car owners or engineers.

Ken
Old 07-13-2008 | 01:03 PM
  #28  
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I usually double clutch. It just feels more natural to me.

I've been trying to learn to incorporate heel-toe into it, but it's still scary and new to me, and I end up missing my rev match target because my speed is constantly decreasing. Theres also the fact that when I'm driving, I'm never entering corners at the kinds of speeds that would require a heel toe downshift. I'm totally cool with doing my downshft 100 yards away from the corner entrance, and I'm fine with only being at 5-6k RPM after doing so. If I was using heel toe in situations where I feel it's really required, I think I'd be far to close to loosing control of the car to be safe on the streets.

People who say "just let the syncro's do their job" are not worried about needing to replace them at some point. Good for them to be making that kind of money.

Last edited by Socket7; 07-13-2008 at 01:09 PM.
Old 07-13-2008 | 01:07 PM
  #29  
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Originally Posted by zero5
Funny. Because I don't see why you all are separating Heel-toing and Double clutching. They are to be used at the same time. If you are double clutching and then braking for the turn you are not gonna be fast. The two techniques are not to be separated. You use the double clutch while you are heel-toing to consolidate your braking distance and your shifting distance before the turn. But I guess I do see how we can just double clutch while on the street during easy driving. But if you wanna learn how to go faster which should be the basis for this thread then one must learn what these techniques are truely for. There is a lot of confusion being dealt out here. The reason I beat half the super cars I race against is purely because these asses who buy supercars don't even know how to drive. By learning the simple Heel-Toe (which includes the use of double clutch) technique you can out brake most possers on the street. It is braking and corner prep that this technique is for. Go download or buy a book on basic high performance driving and instantly wow your friends and destroy Doctors and the like on the street.
Exactly what this guys says... Heel-toe and and double clutching are complimentary techniques to be used together. Individually, they're a skill. Together, it's more like a dance step. Do it right and you can be perfectly prepared for a corner transition, and achieve a level of "smoothness" that would be impossible to pull off without it.
Old 07-13-2008 | 03:57 PM
  #30  
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Originally Posted by zero5
Funny. Because I don't see why you all are separating Heel-toing and Double clutching. They are to be used at the same time.


You aren't always on the brake when you down shift.


For instance, you are on the highway in 6th and need to pass. Do you step on your brakes and do a double clutch heel-toe to downshift to pass someone? Of course not. You just do a double clutch down shift.


And, not everyone can double clutch while doing a heel-toe. Watch some BMI races and you will see that many drivers who heel-toe don't even double clutch. Hell, sometimes the drivers don't even heel-toe. And the drivers on BMI are professional race car drivers.
Old 07-13-2008 | 04:01 PM
  #31  
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Originally Posted by Socket7
I usually double clutch. It just feels more natural to me.

I've been trying to learn to incorporate heel-toe into it, but it's still scary and new to me, and I end up missing my rev match target because my speed is constantly decreasing. Theres also the fact that when I'm driving, I'm never entering corners at the kinds of speeds that would require a heel toe downshift. I'm totally cool with doing my downshft 100 yards away from the corner entrance, and I'm fine with only being at 5-6k RPM after doing so. If I was using heel toe in situations where I feel it's really required, I think I'd be far to close to loosing control of the car to be safe on the streets.

People who say "just let the syncro's do their job" are not worried about needing to replace them at some point. Good for them to be making that kind of money.

It is best to learn to heel-toe without double clutching first. Trying to incorporate double-clutching while learning to do heel-toe is going to over welm you.


Since you already know how to double clutch, just learn how to heel-toe with just single clutch. Once you can learn to single clutch heal toe, then try to incorporate the double clutch into the heal-toe.
Old 07-13-2008 | 05:03 PM
  #32  
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Originally Posted by Chris311
It is best to learn to heel-toe without double clutching first. Trying to incorporate double-clutching while learning to do heel-toe is going to over welm you.


Since you already know how to double clutch, just learn how to heel-toe with just single clutch. Once you can learn to single clutch heal toe, then try to incorporate the double clutch into the heal-toe.
Thanks for the advice, I'll give it a shot and see if my muscle memory gets in the way or not.
Old 07-14-2008 | 04:00 AM
  #33  
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Originally Posted by Chris311
You aren't always on the brake when you down shift.


For instance, you are on the highway in 6th and need to pass. Do you step on your brakes and do a double clutch heel-toe to downshift to pass someone? Of course not. You just do a double clutch down shift.


And, not everyone can double clutch while doing a heel-toe. Watch some BMI races and you will see that many drivers who heel-toe don't even double clutch. Hell, sometimes the drivers don't even heel-toe. And the drivers on BMI are professional race car drivers.
Thats what I ment by easy driving, the highway downshift and stuff. But I never double clutch in a street car. Just like the BMI guys. In battle there is no time for the double clutch to me or the BMI guys it seems (and they don't have to fix them). The only time I or any one NEEDS to double is if you are driving a car with an H pattern box containing straight cut gears. I had to do those painfull shifts in a Formula Dodge car. And, if you happen to get in a car with a sequential box then you don't need it there either because Neutral can only be found under 1st gear. I miss that gearbox. It's like firing off rounds from a cannon.
Old 07-14-2008 | 04:59 AM
  #34  
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Originally Posted by Socket7
Thanks for the advice, I'll give it a shot and see if my muscle memory gets in the way or not.
First off. The magic is all in your pedals! If you don't have upgraded pedal pads then it will be Much harder for you to get it right. That's why it's easier for some than others. The key is to have the gas pedal and the brake pedal as close to each other as safely possible. Some cars come this way for this very topic. Other like my Accord do not. The first mod I do on any car is pedals. I like RAZO but thats just me. The easiest way to close the gap between the pedals is to simply take a piece of 1/8 or 1/4 inch piece of sheet metal and drill that sucker over the gas pedal. Instant race pedals! But check ALL the clearances before and after.

Now on practice. You don't have to be going fast to play with the transmission. Don't be affraid of messing up. Just make sure you practice on familiar roads in LOW to NO traffic.
When it comes to the Heel toe there IS a big difference to me in having the modded pedal and not.
A) With OUT the modded pedal you must usually use the definative HEEL and TOE. Like the BMI guys testing stock cars, you twist your ankle and use your Toes on the brake and your Heel to hit the gas. I have a hard time maintaining consistant brake pressure like this. As I stab the gas with the heel, my toes natually rise off the brake.
B) WITH the MOD pedal. (Practice this while PARKED first!) Keep your foot Vertical, place the BALL of your foot on the Right most EDGE of the Brake. (this will take time to find consitantly). As you press the brake down you will hit the gas due to the new closer pedals. SO, with the ball of your foot in place on the edge of the Brake, you will need to move, your RIGHT, KNEE, to the Left. This rolls your foot to the side letting the GAS pedal pass by as you brake. Now, while we are hard on the brakes our KNEE is still to the Left and the GAS pedal is now just under the right side of our foot waiting to be smashed. The clutch goes in, grab the proper gear, Now quickly swing your KNEE (NOT YOUR FOOT) to the Right! This will naturally roll your foot over on to the GAS pedal, reving the motor. Release the clutch, then the brakes and make your turn and power out like a Champ.
To make sure you get enough Revs for the selected gear, hold your foot on gas and grab A LOT of Revs. Go up to the red each time untill you memorize your ratios. But remember, you are BLIPING the throttle. It's a quick on / off motion. It may be a long Blip at times but it is just a Blip! After the blip let that clutch out. After the clutch is out there should only be pressure on the Brakes!
If you are in say 5th then you should heel-toe down through each gear as you are slowing until you reach the gear you want for the turn. You will find other detail that will become your personal style within all of this.

Don't Be Dead. Be Careful with this.

Last edited by zero5; 07-14-2008 at 05:07 AM.
Old 07-14-2008 | 11:57 AM
  #35  
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Originally Posted by zero5
...With OUT the modded pedal you must usually use the definative HEEL and TOE. Like the BMI guys testing stock cars, you twist your ankle and use your Toes on the brake and your Heel to hit the gas.
What size shoes do you wear? The only car I've ever been able to do that way was a '53 Chevrolet. The pedals on that (linkage coming up through the floor) were very different from modern hanging pedals. Except for the Chevy, I've always "heeled" with the side of my foot.

The 8 is the first car where I've had to move the ball of my foot to the edge of the brake the way you describe. I think that's because the center console prevents me from moving my knee over to the right.

There's a DIY on moving the 8's gas pedal over. Very simple - just unscrew the plate and re-attach using the next set of holes. I was on the verge of doing that until I hit upon putting my foot on the edge.

Ken
Old 07-14-2008 | 02:06 PM
  #36  
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Originally Posted by zero5
Thats what I ment by easy driving, the highway downshift and stuff. But I never double clutch in a street car. Just like the BMI guys. In battle there is no time for the double clutch to me or the BMI guys it seems (and they don't have to fix them). The only time I or any one NEEDS to double is if you are driving a car with an H pattern box containing straight cut gears. I had to do those painfull shifts in a Formula Dodge car. And, if you happen to get in a car with a sequential box then you don't need it there either because Neutral can only be found under 1st gear. I miss that gearbox. It's like firing off rounds from a cannon.

I recommend double clutching in a street car on the street. Since normal driving does not require lightning fast shifts, double clutching will help extend the life of your tranny.

I think the OP was referring to street driving, not thrashing the car around the track like on BMI.

And from what I have read on these forums, the synchros in the RX8 gear box are extremely fragile, so I would highley recommend double clutching for street use to prolong the life of your Synchros as it is a costly repair.


And heel-toe double clutching is still good for track use. Not everyone who takes their car to the track is going to do full throttle upshifts and slaming downshifts like on BMI as most people want to be able to drive home after track day
Old 07-14-2008 | 02:12 PM
  #37  
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Originally Posted by zero5
B) WITH the MOD pedal. (Practice this while PARKED first!) Keep your foot Vertical, place the BALL of your foot on the Right most EDGE of the Brake. (this will take time to find consitantly). As you press the brake down you will hit the gas due to the new closer pedals. SO, with the ball of your foot in place on the edge of the Brake, you will need to move, your RIGHT, KNEE, to the Left. This rolls your foot to the side letting the GAS pedal pass by as you brake. Now, while we are hard on the brakes our KNEE is still to the Left and the GAS pedal is now just under the right side of our foot waiting to be smashed. The clutch goes in, grab the proper gear, Now quickly swing your KNEE (NOT YOUR FOOT) to the Right! This will naturally roll your foot over on to the GAS pedal, reving the motor. Release the clutch, then the brakes and make your turn and power out like a Champ.

THis is how I have always done it (see my previous post about right side and left side of foot), and never with modded pedals, always stock. I had to learn this method as I have had arthritis in my hip since I was a kid and I can't even twist my leg to do a real heel-toe, so I had to learn the method above about using one side of the foot for the brake and the other for the gas.


But then again, I wear 17 size shoes so I don't need the pedals to be close together.
Old 07-14-2008 | 03:03 PM
  #38  
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wow, great info here! Thanks for this.
Old 07-15-2008 | 07:08 AM
  #39  
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I think the OP was referring to street driving, not thrashing the car around the track like on BMI.
Hehe yeah, I was merely talking about rev-matching on regular street driving to save clutch and synchro wear. But thanks for some great info. guys!

God bless.
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