06-IS250

Hey your MT owners,

when your shifting aggressively, do you rev match when down shifting? (IE, when going from third to second, you rev the engine while clutch is depressed, in order to match the RPM that will end up once you go to second, in order to remove that delay and jerk from the car).

also, who here can heel/toe? (its where you have your toe on the brake, and then quickly use your heel to rev match)... i see professional drivers do it, and its DAMN difficult.

i am practicing rev matching right now...i just wanted to know, who does it, and is it hard on the clutch at all? Its fun to practice it.

or any other tricks anyone can teach me regarding driving stick? I am pretty noob (been driving for like 10 months with a stick) and obviously i am 100 % confident in driving in normal conditions, but i have not really practiced any aggressive driving.

how do you guys take off the line?

lets hear it!

mikes rx

iTrader: (14)

I do it all the time on my mustang. It's not bad at all. In fact, it's BETTER to do so, because it puts less wear on the clutch and rest of drivetrain components, because everything will be "meshed" together. Sure, synchros pretty much eliminate the need for this, but it's still better and yields faster downshifts/acceleration.

Some other tips:

1) do not shift through your gears, even with the clutch depressed, when coming to a stop. When slowing to a stop, don't press the clutch in until just before the car starts to shake/begin to act like it's going to stall.

2) do NOT slow down by downshifting. Many people do this because they think it saves their brakes. While this may be true, keep in mind that brake pads are MUCH cheaper and easier to replace than clutches.

3) do NOT rest your foot on the clutch, even if you're not actually pressing on it. keep your foot off the clutch (and hand off shifter) unless you're actually using them.

4) do NOT slip the clutch to hold a car still while on an incline. Just put it in neutral and use the brakes.

5) A general rule regarding manual transmissions: the less number of times you slip the clutch, the longer your clutch will last.


EDIT: Also, technically, I think rev-matching/double-clutching involves actually putting the car into neutral and coming off the clutch to rev it, not just depressing the clutch pedal and revving. This is what helps lower the strain on the tranny components, because it disengages everything for a moment.

stvn

you should ask in the drifting forum. i'm sure someone there would know about heel-toe downshifting and revmatching, if anyone actually posts in that forum

isam250

iTrader: (7)

yehh i do. its a bit harder on the IS cuz the pedals are far apart but yeh i do it

kickin8

iTrader: (1)

yes......the gas pedal is "drive by wire" so it responses a litttle "slow" comapre with other cars and you have to press the pedal harder in order to "compensate"....

D2-AUTOSPORT

I find this method (rev-matching) to be best used when you want to downshift for acceleration, because the car maintains its balance so you can get on the power as soon as your in gear.

If you simply downshift and let the clutch out, the car will buck, then buck again when you slam the gas. If you revmatch the car remains flat and only bucks when you slam the gas.

I can not heel and toe, I always end up pressing down harder on the brake. So I rev-match by goosing the throttle 1 or 2 times and then letting the clutch out to catch the rev's as they come back down.

Its kind of tricky becase if you let go too early, the car will jump forward because of extra throttle, if you do it too late the car will still buck because of lower gear. Its so satisfying when you get it right though. In my car, its easiest to do the 3 to 2nd down shift and revmatch.

kitsune

iTrader: (1)

A few questions.

#1 - Why would you want to lug your engine? Shifting through gears doesn't harm anything even at a stop. There is oil which lubricates the gears and there isn't any load on the gears to make them wear out any more than metal grinding against metal.

#3 - Please explain to me what harm is it in resting your foot on the clutch? The clutch gets pressed all the time when shifting and even when you're not shifting doesn't harm any of the clutch.

Anyways when you rev match it not only saves your syncros but also keeps you in the desired rpm's of that gear rather when you don't rev match you would loss some of the rpm's and your car would lurch forward.

Heel toe isn't something you want to always do. Say when you dive into a corner heel toe is the best technique, however preparing for a corner by rev matching is much better.

I would recommend taking a performance driving school which will teach you and give you experience on a close circuit track to do this legally and safely.

Mike

06-IS250

I did some googling, and I found some answers. but here is my question:

is it ok to downshift to save your brakes? I find it hard to believe that is "bad" for the transmission...

for example, im talking about when your going lets say you are driving along, and your RPMS are at 3000 in 4th gear. you see traffic up ahead, and you start to slow down and then down shift to 3rd and your RPMS are now 4000. is that bad? I do that all the time... usually they dont go higher than 4000 though.

I understand the concept behind rev matching now, but i dont see the purpose unless you are doing "performance" driving. I downshift to slow down usually.

comments?

D2-AUTOSPORT

I use it alot to slow down for "moving traffic", imagine your approaching a highway exit, that also a entrance to another highway, so you need to slow down from 60 to 30 and then go back up to 80, i'll pop out of 4th, rev match to 3rd, and then run back up through the gears when I merge on the 2nd free way.

If your rolling up to the red light, then rev'mathcing is not of much use, (other than hearing your exhaust bark)

Kaydee

well drove a manual before and while i never did learn heel-toe, i can do single and double clutching.

the idea behind rev matching is so that you are in the right gear coming out of a turn, so that you have maximum acceleration instead of let's say 4th > turn > shift to 2nd...it's slower

i used to put it in neutral and brake, not only does that save your clutch, it saves gas, and doesn't make you look like a poser to onlookers

as for resting foot on the clutch, when you do that the clutch disengage a little and the sandpaper material that is supposed to 'grab' the clutch burns the clutch instead...making that burnt clutch smell. overtime, your clutch will start slipping

kinda like riding the brakes, you're not really stopping but overheating the brakes for no reason

kickin8

iTrader: (1)

You can downshift when you want EXTRA breaking power with your brakes (e.g. you need to slow down from freeway speed to 30 mph in a few car lengths).... It wont hurt if you do it once in a while.....

wilwilB

I read the lexus manual it actually recommanded to use engine braking instead of just pushing the braking pad to save up the brake. I know replacing a clutch cost more than the brake but it's what it says in the manual.
I use single clutch rev match all the time when coming to a corner, just brake and put it to neutral when coming to a stop sign or red light.

nukis250

Perfectly on everything he said, My last car last over 100k miles by doing so. Main thing is not press on the clutch while waiting on the red light. friend does that and end up changed his clutch at less than 12k miles.

Recluse

I know enough not to rely on Wikipedia all the time, but this describes it WAY better than I could:

http://en.wikipedia.org/wiki/Riding_the_clutch

Recluse

I may not explain this very well, but consider that if you downshift without rev-matching, you are really creating more clutch wear. That's because, as in your example, in order to transition smoothly from 3000 RPM to 4000 RPM, you have to release the clutch pedal much more slowly than usual, or else your car is going to lurch forward as the RPMs go up.