yea, but is rev matching with the clutch pedal down cause faster wear on the clutch, or would it be better to double clutch?

 

I always thought that "heal and toe" was followed by "dosey doe"

 

After reading all of the above, I am glad none of you are my students at drivers schools. First of all unless you are extremely experienced at high speed driving you do all of you braking in a straight line. During that time you will also be downshifting using the heal and toe method. Best done as stated by some already as ball of foot on brake, compressing pedal as hard as possible to a point just before lockup (threshhold braking). At the same time you roll the foot to the right and using the side of your foot blip the accel. pedal to bring the revs up to the point you need when the clutch is let out. The clutch in, shift, blip and clutch out is one to two seconds in length. No excessive wear on clutch and strain taken off of tranny. Ease off brake and start turn in. Start to apply gas and be at full throttle at apex if all is done right. If car is pushing during turn in, than try trail braking. Brake while turning to help rotate rear around. If double apex corner you can lift off gas and than back on to rotate.

All very simple. If any of you are in the South Florida Area you should join NASA and come out to our track events at Homestead, Moroso and Sebring. All of us instructors are very willing to work with any student in driving techiques.

Jay Goldfarb
Silver 8
Wellington, FL
Ex SCCA, SVRA, BMWCCA & POC racer

 

After reading all of the above, I am glad none of you are my students at drivers schools. First of all unless you are extremely experienced at high speed driving you do all of you braking in a straight line. During that time you will also be downshifting using the heal and toe method. Best done as stated by some already as ball of foot on brake, compressing pedal as hard as possible to a point just before lockup (threshhold braking). At the same time you roll the foot to the right and using the side of your foot blip the accel. pedal to bring the revs up to the point you need when the clutch is let out. The clutch in, shift, blip and clutch out is one to two seconds in length. No excessive wear on clutch and strain taken off of tranny. Ease off brake and start turn in. Start to apply gas and be at full throttle at apex if all is done right. If car is pushing during turn in, than try trail braking. Brake while turning to help rotate rear around. If double apex corner you can lift off gas and than back on to rotate.

All very simple. If any of you are in the South Florida Area you should join NASA and come out to our track events at Homestead, Moroso and Sebring. All of us instructors are very willing to work with any student in driving techiques.

Jay Goldfarb
Silver 8
Wellington, FL
Ex SCCA, SVRA, BMWCCA & POC racer

 

By rev matching, you're doing 60 behind someone you want to pass, in 6th, 60 is what? 3700-4200, you down shift, rev the engine to 6000 and feather the clutch. Instant power and noise, they usually take notice of the increased DBs and move over, you punch it and in a few seconds your going 90+ and coast down to 70, 80, 85, what ever your cruising speed is and reingage 6th to save gas. I have increased my mpg a lot by staying in the highest gear not to bog the engine whenever possible and making very aggessive downshifts to still have fun.

 

Another heel-toe video for those interested..this time in a miata.

(Last video on the page)

http://www.chrisgreer.com/work.html

 

I always shift down from 6th to 2nd when turning into my driveway; brake-clutch in-shift down-clutch out-turn. I've been doing this on all my cars for 20 years. Is this bad in any way?

Also I still do not understand the purpose of double clutching when shifting down to overtake/accelerate. Why can't I just rev up the engine to the appropriate rpm just before, or as I let out the clutch after down shifting? I always do this when I'm approaching a fast sweeping curve and I want to keep up the speed and get tighter control of the car around the curve. i.e. clutch in-shift down-rev match-clutch out. Is there anything wrong with what I'm doing? As far as I see it, double clutching would slow down the process and be not as fun.

I can understand the purpose of heel-toe shifting though, when you need to brake without losing engine speed and torque when going round a corner. But double clutch? Any expert opinion on this?

 

My amateur opinion is that double-clutching is simply a hold-over from the old racing days when primitive synchros - or none at all - made double-(de)clutching a requirement for smooth shifting. Many cars occasionally require a double-clutch to engage reverse (like my Eclipse), but never for forward gears.

Old traditions die hard, even though the underlying reasons for it's existence are long gone.

Still, people will say double-clutching prevents synchro wear. I suppose it does, but I've never worn out synchros in any of my cars.

Rev matching, on the other hand, is critical to extending clutch life, as well as allowing smooth shifts.

 

The key to speeding up on the outside is slowing down on the inside. As Jay mentioned double clutching is done while braking on a straight prior to the turn. when you are done you should be in the gear you plan on exiting the turn with.

Double clutching is more than rev matching. There are three parts that are being matched, The engine, the transmision and the final drive.

As for wear, I learned this procedure in 89 from Bob Bondaurant's course. I have used it since then and the only clutch I have replaced was the one in my 89 convertible RX-7 with 170000miles on it. I also used that car to tow my 82 ITS RX-7. I got some looks showing up at the track like that.

Trackter trailer rigs use double clutching to upshift as well as downshift.

John

 

I fear this may be misleading for new track drivers.

Double-clutching is not necessary for smooth downshifts. The synchros will do the work for you. In fact, on the track, I don't know why anyone would want the additional distraction of double-clutching. Why downshift 3rd-neutral-2nd when 3rd-2nd works just as well?

Double-clutching doesn't make the downshift any smoother (on modern synchro cars), hence it has no performance benefits on the track.

Rev matching via heel-and-toe, however, is critical when downshifting for (or into) a corner to avoid overloading the already overworked tires. Whether you accomplish that downshift directly from gear to gear, or by including the extra step of pausing in neutral (double clutch), the end result is the same.

 

Enough already.

Just press hard on the brake and give the gas a blip with the side of your foot to match revs (takes strain off of trany and keeps your from upsetting the balance of the car and shift quickly. Double clutching is not necessary unless you are driving an old non synro car. Power into and out of the turn.

Remember one thing... Slow in - Fast Out
... Fast in - Dead Out

 

If it doesn't make the downshift smoother for you, then you're not double-clutching right! (I'm referring to the actual movement of the shift lever to the lower gear). I will always agree that it has no performance benefits, but it does have durability benefits. Synchros do wear, and can wear out (Ever driven a RWD Alfa? Notorious for bad/weak 2ng gear synchros). Not often or easily, but it is possible. Double-clutching downshifts pretty much eliminates synchronizer wear. They're also fun! :D

Regards,
Gordon

 

It seems alot of people hear shift heel2toe.... How come in real life when i metion this, nobody has any clue what im talking about? oh well....... The less people who know the faster i seem.

mmamwmahehAWHAHWHAHW

 

what's the difference between double clutching and just matching revs?
like when I want to downshift to pass on the highway, I
step on clutch,
shift from 5th to 3rd,
step on gas to match revs,
let go of clutch.

what does the extra step on clutch, move to neutral, let go of clutch THEN match rev does?

 

I only double clutch when I downshift to 1st

 

It's really called heel-and-toe. It is basically a downshift technique, to be used in conjunction generally with heavy breaking. It is used under spirited driving conditions, track conditions, etc. Most drivers that aren't into performance driving or performance driving techniques will probably not be aware it.

 

The extra rev-blip in neutral with the clutch out brings the clutch disk and transmission input shaft up to speed before putting it in gear. In the days of no synchros, or weaker synchros, double clutching was necessary. Today, with modern transmissions, the synchros are very good and durable, so the double clutch isn't really necessary. Of course, you can double clutch to give your synchros a bit of a break.

 

thanks
yea I think I finally got the double clutching down after a bit of practice! but you guys are right, the shifter almost sucks itself into gear when I blip the throttle in neutral and clutch out before picking the down gear! very smooth

 

Nope, car is built for that. My instructor at the Mazda Prodrive in the UK told me to skip gears whenever possible.

 

I am assuming that where you live, transmission systems are cheaper then brakepads......

 

I started heal-and-toe(ing) back in high school ('bout 24 years ago) out of necessity. That Opel GT had the worst carb (Solex)... so that it wouldn't even idle (rebults too). The only way to brake and not stall was to be able to manipulate the throttle at the same time. Changing to a Weber carberator fixed the issue... but once you learn the heal-and-toe technique, I never looked back.

I don't care if you're breaking hard or light, coming into a turn or up to a stop light... A downshift, no matter if it's to the next gear down or skipping gears, should (in the name of fun and to save wear and tear) be done using heal-and-toe to "rev match" the crank shaft with the drive shaft.

I really can't recall driving a car without doing this - always - every downshift - which is nearly every time I slow down. I do know that doing it barefoot takes getting used to (I don't do this much). And, when I'm wearing brand new shoes... it takes a little while to become accustomed to the feel.

I admit to doing this backwards. I use my heal for the brake, and the toe for the gas. Mostly, because I feel most comfortable pivoting my toes to blip the gas. I feel this gives me the most control. The "official way" which I've read through this post from the racing school quote is the other way around.

The most difficult thing about driving a new car is knowing how much "blip" to give the gas.

I feel sorry for people with big feet. I don't know how you do it. I'm only a size 8. Must be like watching a basketball player try to fit themselves into the booth at McDonalds.

 

Funny Zeltar - I heel-and-toe my MG all the time for much of the same reasons: so-so brakes and questionable idle. But, then again, it is a british car...

I only heel-n-toe the 8 under moderately heavy breaking, or downshifting for an impending turn...

I use the side-of-the-foot variation. Ball of foot on the brake, and rotate foot sideways and blip the throttle with the side of the foot.

 

LOL. I had an 87 VW Cabriolet that had the same problem. If the car idled, it would die. I didn't have the foresight to learn to heel and toe unfortunately. When braking for a stoplight, I'd brake with my left foot, keeping the right foot on the gas and shoving the shifter into neutral. Since the car wasn't a good performer, I never learned how to properly heel-toe downshift for corners, so I still need a lot of work at that.

 

Mk, so after about two years, anyone get it down pretty good? After about 1 month (of getting used to the 8) i started to practice it. It's been about 7 months of practice, and i can honestly say (i don't practice it allllll the time, just like a few times each drive, but including my 'track' days where i really put it to test) I can get it about 7-8 out of 10 tries.

I'm a size 9, so i dunno if it's easier for me? But i just like doing it, you can really tell when you do it right, and when you don't do it right. I do it in the city just to keep myself from getting rusty? Don't wanna suck at it, just until the days where i can put it to full test.

Anyone getting it down?

 

Actually, good truck drivers rev-match so well that they do much of their upshifting and downshifting without using the clutch at all. Many of their transmissions dont even have synchros. But also, their diesel engines redline at like 2,000 RPM.