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"heel-and-toe" & "double-clutch"

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  • "heel-and-toe" & "double-clutch"

    Ok, here is a definitive guide to what these mysterious terms actually mean, and how to use them.

    HEEL-AND-TOE:

    This is a technique used mainly while racing, rallying, or in timed motorsport events. It is used to downshift smoothly and quickly at high speeds without upsetting the balance of the car. It reduces the stress on the gearbox hardly at all, so don't think you are saving your car by merely heel-and-toeing. I'll get to gearbox-saving techniques later.

    These two images show how to place your feet to heel-and-toe. The first one is the "classic" heel-and-toe, used in older cars where the pedals are spaced out enough that you actually need to use your toe and your heel to bridge the gap between the pedals. The second one is a more modern approach, used in a car with pedals that are close together (ie. well-placed pedals).





    Imagine you are in fourth gear, approaching a medium speed corner that requires you to be in third gear. If you ram the gear lever into third, and dump the clutch, the car will lurch, and has a good chance of losing traction and sliding. This is also known as the "shift-lock" drift. Great for getting a car sideways, but not good if you want to go fast, and you want your gearbox to last. Here's what you do:

    1. Start braking, with your feet in the position in one of the diagrams above.

    2. Push in the clutch pedal

    3. Bring the gear lever out of fourth gear.

    4. While braking with constant pedal pressure, roll your foot over and blip the throttle to match the engine speed with the road speed (this takes a bit of practice).

    5. Place the gear lever into third gear.

    (steps 3, 4 and 5 should be done as one fluid motion)

    6. Let out the clutch.

    7. Let off the brakes and turn into the corner.

    This is how you "heel-and-toe." A good tip is to adjust your pedals so they are closer together. One way is to bend your throttle pedal so it is closer to the brake pedal, and another is to fabricate an extension for your throttle pedal (this is preferred over a brake pedal extension, because if your extension fails, it would be better when you are using the throttle as opposed to threshold braking and all of a sudden having your foot plow past the brake pedal. Since your foot is hovering over the throttle, your foot would suddenly pin the throttle to the floor. Not a nice feeling when you are approaching a fast corner with minimal run-off area).

    DOUBLE-CLUTCHING:

    This technique was initially used in vehicles that did not have synchromesh gearboxes. Check out http://www.howstuffworks.com to learn how a gearbox works. (note: synchros force the input shaft and the output shaft to spin at the same speed before the dog engages the gear on the output shaft)

    Basically, the aim of double-clutching is to synchronize the speeds of the input shaft and the output shaft. This is required in gearboxes that have no synchros, but it also adds to the life of a synchromesh gearbox as well by taking the stress off the synchros and allowing the engine to synchronize the shaft-speeds instead. This technique can ONLY be done when heel-and-toeing (unless you take your right foot off the brake to hit the throttle, which would be a bad idea).

    This can be used on upshifts and downshifts. On upshifts, double-clutching slows down your shifts greatly, so it is not favourable. However, if you start to experience gearbox problems during a race, you may want to try it so you can at least finish. On downshifts, it greatly reduces (and almost eliminates) the stress on the synchros, and there isn't really any time lost, as you are braking anyway. This technique is EXCELLENT for endurance racing, and as long as you are paying the bills, it is excellent for anyone who wants their gearbox to last as long as possible between rebuilds.

    Here's how you do it.

    Upshift:

    1. Push in the clutch pedal.

    2. Pull the gear lever out of gear, and into neutral.

    3. Let out the clutch pedal

    4. Allow the revs to drop to their approximate speed in the next gear (ie. if you are at 7000 rpm in fourth gear, and at that same speed, you would be at 6000 rpm in fifth gear, allow the revs to drop 1000 rpm)

    5. Push in the clutch pedal.

    6. Select the next gear with the gear lever.

    7. Let out the clutch pedal and continue accelerating.

    This is slow. Don't do it unless you have serious gearbox problems.

    Downshifts: (same idea as the scenario for heel-and-toeing... 4th to 3rd downshift)

    1. Start braking with your feet in the same position as one of the two diagrams.

    2. Push in the clutch with your left foot.

    3. Pull the gear lever out of fourth, and put it into neutral.

    4. *Let out the clutch pedal*

    5. While braking with constant pedal pressure, roll your foot over and blip the throttle the required amount. (ie. heel-and-toe when the clutch pedal is out/clutch is disengaged and the gearbox is in neutral)

    6. *Push in the clutch pedal*

    7. Select third gear with the gear lever.

    8. Let out clutch pedal, and continue braking until your turn-in point.

    (note: double-clutching is impossible in cars with sequential gearboxes, because you can't select neutral between each gear. Once the gearbox shifts out of one gear, it shifts into the next gear at almost the same time)


    This is everything you need to know about heel-and-toeing and double-clutching. Forget what your ill-informed friends told you, and forget what some guy on the "Fast and the Furious" apparently said.

    Try it on your car, and practice each technique. It will help you drive smoother at the limit, and it sounds really damn cool when you heel-and-toe when approaching a corner.

    Here is a good video of a pro using the heel-and-toe technique (without double-clutching): Michael Vergers in a Radical SR3 Supersport
    Last edited by malcolm; 09-28-2004, 11:16 AM.

  • #2
    Malcolm, Well said homie... Hopefully one of these days, you can get a major sponser here in the states to sponser you to drive over here...

    So how are these techniques used for drifting? if you don't mind elaborating.

    Matt.
    Last edited by Craftsman; 09-27-2004, 11:04 PM.

    Comment


    • #3
      very well written. hopefully this will prevent a lot of "wuts double clutching" threads :P sticky perhaps?

      Comment


      • #4
        I was just about to ask you this today. I was practicing that very technique in an old 4-speed F150 a couple of days ago. At one point in time it was something I thought I'd never do, so when I pulled it off for the first time I was ecstatic. I've got a long way to go though, it was far from being smooth and comfortable for me.
        p.s. I

        When I drive normally, though, I do a variation on it. (Keep in mind this is in a 4x4). I let off the gas completely and put my right foot on the brake, left on the clutch. After I've slowed enough, I put my right foot back on the gas and slowly release the gas as I gently feed in the throttle. I've driven stick my entire life without heel-toeing and haven't had any trouble, but then again this is a truck so I can feel what the thing is doing alot easier than in a sensitive racecar.

        So just to make sure I've got the right idea, you do all your downshifting BEFORE the turn in, then it's clutch in, downshift, blip, clutch out right?

        Comment


        • #5
          Just to let you know malcolm, you posted the same heel-toe classic picture twice in your post. I assume you were talking about the side of foot-toe and ball of foot downshift technique. Let's just call it SF-TBF D.. or just heel-toe.

          Here is a step-by-step analysis i posted a while ago in another thread. Hopefully if you don't understand malcolms, this might fill in what you don't understand.

          let's say your redline is at 9,000 rpms and when you upshift the revs drop down to 7,000 rpms. now you're at the track in 4th gear at 9,000 rpms and you are approaching a corner. a second gear corner. this is what you do normally with good synchros:

          1. foot on the brake, wait for revs to drop to 7,000 rpms
          2. clutch in
          3. blip throttle, rev up to 9,000 rpms
          4. downshift to 3rd
          5. clutch out
          6. wait for revs to drop to 7,000 rpms
          7. clutch in
          8. blip throttle, rev up to 9,000 rpms
          9. downshift to third
          10. clutch out, and take the corner

          this what you do with bad synchros, i mean REALLY bad synchros

          1. foot on brake, wait for revs to drop to 7,000 rpms
          2. clutch in
          3. shift to neutral
          4. clutch out
          5. blip throttle, rev up to 9,000 rpms
          6. clutch in
          7. shift to 3rd
          8. clutch out
          9. wait for revs to drop to 7,000 rpms
          10. clutch in
          11. shift to neutral
          12. clutch out
          13. blip throttle, rev up to 9,000 rpms
          14. clutch in
          15. shift to 2nd
          16. clutch out


          see the difference?

          now lets look at double clutch upshifting
          you have turned the corner and you exit at 6,000 rpms in 2nd gear... this is what you do normally with good synchros

          1. foot on accelerator until revs up to 9,000 rpms
          2. foot off accelerator
          4. clutch in
          5. shift to 3rd
          6. clutch out
          7. foot on accelerator

          this is what you do with BAD synchros to double clutch

          1. foot on accelerator until revs up to 9,000 rpms
          2. foot off accelerator
          3. clutch in
          4. shift to neutral
          5. clutch out
          6. wait for revs to drop to 7,000 rpms*
          7. clutch in
          8. shift to 3rd
          9. clutch out
          10. foot on accelerator

          *not only is this technique slower and much more complicated, but during the time of your shift wand waiting for revs to drop, you lose speed, sometimes even four or fives times as much speed as tou lose in normal upshifting. so now you should see that this technique is slow and bad (but good for synchros) and good synchros are key to winning races and easy driving all the time.
          Last edited by scirocco; 09-27-2004, 06:36 PM.

          Comment


          • #6
            I posted this in some irrelevent topic in New to drifting, but here.



            here's some video:

            http://flipty.com/leadpipe/gtipics/feet.avi

            Right click, save as.

            Comment


            • #7
              thanks for the heads-up scirocco... I just forgot to change the file name when I copied and pasted...

              and just so you know, in your description of heel-and-toe, you said downshift to third twice, instead of second.


              ---------------------------


              Double-clutching can't really be used for drifting, because its primary aim is gearbox longevity, and offers no other benefits. Heel-and-toe can be used to keep the car stable. It won't help initiate a drift, but it could help you be more precise on your entry to a corner, thus allowing you to have a better line through the corner.

              My main aim for this thread was to prematurely answer all the people who ask it without searching.
              Last edited by malcolm; 09-28-2004, 11:25 AM.

              Comment


              • #8
                lol so I guess that with the correctness of your article, and the correctness of my step-by-step comparison (and the wrong parts) there is a completely correct superarticle right? Like attaching two ferraris together at the door. That would work right?

                Comment


                • #9
                  Please add "turn in" point to your heel-toe steps.

                  Thanks for the heel-toe instruction. I've been practicing for weeks and showing improvement. I've been going over the technique in my head as much as doing it in the car. This has led me to sub-divide heel-toe skills into different sets.

                  Low RPM normal driving requires smaller throttle blips.
                  Higher RPM driving requires larger throttle blips (more pressure).
                  Straight line heel-toe-ing is a different flavor from cornering heel-toe-ing, the latter requires more coordination and better timing.
                  Each downshift in high and low RPM and straight and cornering can be said to have different attributes. In a 5-speed, that's 16 iterations.

                  This brings me to the header line for my post. Here's my perspective - search it for problems: How aggressively I approach a corner determines the usefulness of heel-toe.

                  Scenario 1: wimpy approach, 90 degree corner
                  I simply heel-toe while decelerating on approach to the corner. The engine braking and pedal braking combine through each gear to give easy deceleration. It's good practice for foot positioning and throttle blipping, but doesn't shave off time.

                  Scenario 2: moderate approach, 90 degree corner
                  This is when I've got some extra speed and am "paying attention" so to speak. I do the following, from 60 mph:

                  1. clutch in & toe on brake down to 50, lever out of 4th to N
                  2. shift into 2nd (this is in an SR5, not an Indy car) as soon as practical before turn in, time it so I'm at 40 at turn in for this particular corner.
                  3. Blip throttle, let out clutch, and let off brake and EXCHANGE threshold braking for lesser effect engine braking during the first half of the corner.
                  4. hit the gas at apex, having been in the appropriate gear for the corner since turn-in.

                  Scenario 3: racing approach to 90 degree corner
                  Serious business - but still okay to laugh at my developing technique.

                  1. clutch in & toe on brake down to 50, lever out of 4th - N
                  2. threshold brake to turn-in, shift to 2nd
                  3. carrying so much speed that I exchange threshold braking for reduced pedal braking INSTEAD of exchanging threshold braking for engine braking. --still need substantial decel in 1st half of corner.
                  4. on approach to apex, blip throttle, let out clutch, & hit gas at apex - full throttle out of the corner.

                  There is no ego here: get it straight that I get scenario 3 timed correctly only about 1 out of 8 tries, up from 1 out of 20. Whoever said it takes time to develope these skills was not kidding.

                  Comments welcome. Thanks guys. Thumbs-up to fun times behind the wheel.

                  Comment


                  • #10
                    I think you may be better served to improve your braking, and then add in heel toe when you are consistantly achieving good brake modulation and timing.

                    Comment


                    • #11
                      Hey, I was wondering when using heel toe from like 5 or 4 gear, is it better to go through all the gears to get to 2? like i notice in all race videos when they heel toe they actually go through all the gears. I do that as well like 4 to 3 let out clutch then 3 to 2 let out clutch. Is skipping gears better? I notice though that all the pros in videos go through the gears as well, so is what im doing a good practice or should I start skipping gears like 4 to 2 and just do a giant blip on the gas pedal?

                      Comment


                      • #12
                        Usually you cant anyways. Get your car at say 4th gear speed, then hold in the clutch and try to push it into 2nd, usually the transmision wont let you. At least this how it is on the the cars ive driven.

                        its just easier to gear down through the gears, then hold it at and wait for it to go in, fFor me at least.

                        Comment


                        • #13
                          Yea, it only does that on my 1 gear. My other gears I can go in at anytime, so I can skip around if I wanted to, but I've never done it that way, but like what jasonaries said, he went from 4-N-2 and so I'm just trying to clarify which is proper, like for me I use the separate gear shifts from 4-3-2 as a way to measure my gas, like I blip the same from 4-3 then blip same from 3-2 so it is constant unlike a large blip from 4-2 or a smaller blip from 4-3. I kind of just figured that on my own, but I'm guessing thats what the many blips are for? to measure and remain constant throughout shifts? I'm not too sure, but yea, so if anyone wants to clear this up for me. I mean it works for me, but maybe there are better ways out there.

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                          • #14
                            Bottom line i think the end result is pretty much the same. Its jsut driver prefernce. Yo ucan argue your in your power band longer by going through the gears, but your clutch is only in for a moment, and your trying to brake anyways so you dont -need- to be in your power band.

                            Either way your going to end up going X mph in 2nd gear at X rpms.

                            Do whichever is easier, hoenstly for me itd be easier to jsut go down through the gears. Less to think about, as you can do it moment to moment, instead of waiting and thinking about it. Maybe letting you concentrate on taking your line that much more. doing it by "feel" ya know?

                            Comment


                            • #15
                              Now I have only driven standard once and that was just around the block, so I do not claim to have much authority on the subject, but I can imagine how even though it may seem easier to skip gears, for me I can imagine how heel and toe would become second nature eventually so skipping gears would not be helpful. And, as was said, taking the correct line and timing your braking and throttle are very important so as much concentration as possible must be diverted to this.

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