Heel / Toe
Written by George Roffe
This subject has come up almost as much as fifth gear pop-out recently. So....
First of all, the purpose for downshifting before a corner is to engage the proper gear for *exiting* the corner. You should *never* use the engine's compression for braking. Besides, you should be able to brake a lot harder and faster than the engine could ever hope to contribute to slowing down.
Done correctly, your braking will be as smooth as if you took the car out of gear or didn't downshift at all. The nose of the car should *never* bob up and down as you heel and toe. If this happens, it means your braking is uneven and you are not braking as hard as you could. Also, if you use trail-braking into a corner, you will upset the balance and handling of the car. This means you cannot corner at the limit of adhesion (or if you are at the limit, you will likely spin).
Heel/Toe braking is taught both with double clutching and single clutching. Double clutching comes from days gone by when gearboxes were more fragile and synchros didn't last. Using double clutching, as you brake, you press the clutch, take the car out of gear and let out the clutch. You then blip the throttle to bring the input shaft of the gearbox up to the proper speed to mesh with the output shaft (for whatever gear you are selecting). Press the clutch when the revs are matched, select the new gear, let out the clutch. Repeat as necessary.
The modern method is single clutching. This was used by the pros before rev matching was built into racing engine management software. It is also what is taught at racing schools. Using single clutching, as you brake, you press the clutch, blip the throttle to match revs for the next gear, select the gear, and let out the clutch. Repeat as necessary. Single clutching relies on the synchros to mesh the gears (I think I recently posted the opposite, duh < 8^ ( - sorry).
The trick most people have a problem with is working the brake and throttle at the same time. Done properly, you put the whole ball of your foot on the brake (don't cheat and put half on - if it slips off under threshold braking, or you miss entirely, you are likely in big trouble), turn your foot partially sideways until it is over the throttle, and turn your ankle to use the *side* of your foot to blip the throttle. It feels weird at first, but gets better as you gain experience.
This brings up the subject of pedal placement. Everybody likes something different. There are a number of ways of changing the spacing between the brake and throttle pedals. That's another subject and I won't cover it here. I used to like the pedals closer together than I do now (in fact, I think the SE-R classic has ideal placement). When I attended the Spenard David Racing School (now the Bridgestone school) I asked for the pedals to be adjusted closer together. They would not do it. The reason is the brake pedal, when fully depressed, should still be higher than the gas pedal. This way, when under threshold braking, you minimize the risk of pressing the gas too, upsetting the car, or extending your braking zone.
Remember, your first priority is braking. Also be smooth. Your front end should NOT bob up and down. Your braking distances will probably be longer at first, so keep this in mind. When practicing, don't brake any harder than you can without bobbing (dumb, driving over your head!). As you get used to it, you'll be able to brake harder and harder until you can brake just as hard either way.
Sorry for the long post, but these questions keep coming up. It's not SE-R related specifically, but we might want to put this into the FAQ, since it comes up all of the time.
Enjoy the ride,