jvils

Heel/Toe is used in road racing to smoothly shift to lower gears while braking for a corner. I do it on the street all the time to practice, and 'cause I love the sound and the feeling of perfect shifts under braking. Blipping the gas also makes the shift easier on your synchros, so it is better to do it just before selecting the lower gear and engaging the clutch. The best way to learn how to do it smoothly is to do it while slowing down, but not while braking. Learn how to match the speed/gear/blip with just the clutch and gas, then start adding brake (with your toe), and blips (with your heal or with the side of your foot). It took me a few weeks to get the mechanics down, and a couple months to get any good at it (and it's still debatable whether I am good at it).

I've never heard of rev matching up-shifts; if you're on the gas at all during an upshift, it's pretty much a power shift.

Also note, I find it much harder to do this smoothly on the street 'cause you don't need much of a blip. I have a video of me driving at Sebring last saturday, and you can hear all the downshifts. Here's a link if anyone's interested (22meg, 5:30min, 2 laps, chasing a 944T Porsche).

http://www.sandrino.com/s2k/CMS_Sebring_02.mpg

soundzero

Thanks for sharing that video with us.

I will be in Mid-Ohio race track on 23rd. I have been practicing Heel-toe braking ever since I got my S2000.

Time to put practice to the test.

xviper

People have this idea that "rev matching" must be associated with "blipping" the throttle. This is not necessarily the case. Most see it as something you do when downshifting and thus, the "blip". However, when you upshift, by simply lifting off the gas and waiting for the precise moment when the revs come down to the "proper" speed before you engage the clutch after the upshift, you are "rev matching".
After you shift, the input shaft of the tranny is spinning at a certain speed (which will be different than the previous gear you were in). The input shaft speed is governed by how fast the rear wheels are turning. Now, the idea is to get the engine speed (flywheel) spinning at more or less the same speed as the input shaft at the moment the clutch engages and connects the engine power to the rest of the drivetrain. If the two are spinning at vastly different speeds, that is when you get the lurch.
Which do you suppose would hurt your hand more:
If you put it against a wall while you are driving at 30 mph past it or if you put your hand on that wall when the wall is mounted on the side of a semi also going 30 mph next to you?

samjabori

thanks guys. my bad. no more upshift rev matching from now on

one case study:
i am in 3rd gear, say, at 50 mph and 5k rpm. disengage clutch, rpm drops to approx. 1.5k, shift into 4th, engage clutch, rpm climbs to approx. 4k. just by judging from the rpm , is this smooth? i mean, if i disengage clutch, push the gas pedal till the rpm climbs to 5k or 6k, shift, when the rpm drops close to 4k, engage the clutch, and if i am lucky, the rpm will stay at 4k. thus eliminating the climb from 1.5k to 4k.

anyways, since the consensus seems to regard upshift rev matching as not necessary, i will take it and focus on downshift rev matching and happy driving....

xviper

[QUOTE]Originally posted by samjabori
thanks guys. my bad. no more upshift rev matching from now on