Heel-Toe on track
 

Hey Guys,

I was wondering if you come up to a corner that you could take with 30-35 mph but you were initially at say 7mph. Do you just brake until you hit the 30-35 mph and heel toe? I found that its quite hard to downshift into gear right after you blip the throttle. I always have to shift first then blip then clutch out.

Sorry if it's too vague, let me know and thanks! :burnrubber:

The idea of heel-toe is two-fold: first, you allow the engine deceleration to act as additional braking force. Secondly, you complete the shift to a lower gear while braking so you don't spend time coasting after the brake zone getting into the right gear before you get back on the gas.

So, usually I'll start my braking to get the balance of the car right, and once the weight is transferred to the front of the car, I'll move my heel over and give a quick blip while moving the shifter to the lower gear, then let the clutch out. The key is to get as close as possible to a perfect rev match so you don't jerk the car by letting the clutch out. In an extreme instance, you'll lose the back end doing this and end up giving a hokey pokey clinic by turning yourself around.

Here's a video of me messing around in my Lemons car showing plenty of heel toe action:

[ame="https://www.youtube.com/watch?v=UJH3yU5TmUw"]Driving the Lemon at Putnam Park - YouTube[/ame]

Let me know if you need me to clarify anything.

The more you slow down, the larger blip you need. How you come off the clutch is probably the most important part of the whole mess.

Heel and toe
 

I guess I just don't really understand because I would see some ppl heel toe twice for a single corner. but base on what you did. even if you are in 5th gear you could slow down fast enough to go from 5th directly to 3rd? Is it more like predicting what speed range you are going to be in during the initial brake like you said as the weight of the car is transfer to the front then you heel toe according to the speed at that moment? and also I think what you did was you blip after you first shift to the lower gear correct?

This is usually due to styles. Some people rev match through the gears (what I do personally), others would go 5th-3rd. It's all personal preference.

wouldn't going through the gear waste more time and increase your chance to corner not as precise as you wanted it to be?

If you're doing it while slowing down still, there is no lost opportunity that you could be accelerating instead. It truly is an art that takes years to get down just right.

You meant if I have to slow down anyway there is no loss of acceleration opportunity right?

It's just that some corners don't require that big of a brake which render me in a weird feet position to heel toe.. Especially driving around town

Always go into the gate, even if you don't let the clutch out. This will reduce wear on your synchros, and extend transmission life.

In the Putnam video, I'm never in fifth. It's always 4 to 3 in T-1 and 3 to 2 in T-7. I will do multiple heel-toes in a corner if I'm going down two gears, ie. at Mid Ohio.

It takes a lot of practice. A lot. Everyone develops habits, especially while driving, and learning to heel-toe feels awkward at first because it just doesn't feel right. It's not something that just suddenly "clicks" and you're a pro. Practice...

If you're only slowing a small bit, you may not need to downshift at all. You can bleed off speed simply by turning into the corner, the tire's lateral friction will chew off a few mph. If this makes you fall out of the power curve to exit the turn, then you may have been in too high of a gear to begin with. A heel-toe downshift can be performed very quickly with enough practice.

Learn to pivot your foot around the brake pedal without changing how much pressure you're applying. Even if it's light pressure. The exact motion and placement you feel comfortable with can vary, but typically you use the inner ball of your foot to brake, and the side of your heel to blip/rev the throttle (as mentioned above). This constant pressure is easier to apply under hard braking, but takes more skill and sensitivity under light braking.

If you're braking you can downshift as many gears as necessary, as long as it doesn't prevent you from accelerating when you need to. I also prefer to downshift single gears one at a time as I'm slowing down.

Heel toe
 

I'm just a little confused now. It's been really good help from you guys. So say I'm at 50mph and I slow down for a corner and not knowing what's the proper speed. Wouldn't it always be good to shift to a lower gear? For ex. Like going through all the gear till like maybe 2nd gear since I take most street corners with 20 mph? Lower gears give you more torque right?
And do you shift into gear before you blip?:thanks:

My go-to video clip when anyone asks.

[ame="http://www.youtube.com/watch?v=VxGtx9xXhlM"]Heel and Toe Braking - Shifting Technique Tutorial: Hooked On Driving - YouTube[/ame]

^This.

It just takes practice. It's like driving a manual for the first time. You stumble and stall, but once you get the hang of it, it becomes second nature.

If you're approaching an unknown corner, you will naturally slow to a speed you're comfortable with, a speed that gives you enough confidence that you'll have time to react to any more unknowns. That being said, driving around the street is a far different mindset than driving on the track, where repetition builds familiarity and you naturally begin to push for later braking zones, more aggressive throttle application, better lines, and better lap times. The street is no place to push the car's limits (or your own), but certain techniques can be practiced, such as heel-toe.

As far as choosing which gear, it's entirely up to you and what RPM you want. At the track you may rarely be below 4k RPM, whereas on the street you may rarely be above 6k. There's too many variables to say "do this" or "do that" for any situation. If you're trying to keep the car "in the powerband", you typically want to keep it somewhere above 4k where the power and torque pick up. So as you are braking, if the current gear drops below 4k, you can downshift to keep the engine in the sweet spot. If you need to continue braking (and again the engine drops below 4k), downshift again. This may all happen over the course of two or three seconds.

Watch as many videos as you can to see how it all works together:
apply brake
clutch in
shift into lower gear and rev match to proper rpm (using your heel)
clutch out

KKaWing's video above describes it well, and trippinbillies40's video shows it in practice (watch his tach when he downshifts). Personally I was mesmerized by the pile of dirt rolling around the passenger footwell, it was hypnotic, lol

Lower gears do provide more torque, but it's relative to engine RPM. For instance, 2nd gear at 2000 RPM might feel sluggish compared to 3rd gear at 6000 RPM. But, both gears at 6000 RPM, 2nd will feel a bit stronger, but 3rd will carry the car to a higher speed. Ideally for performance driving or racing, you want to be at the beginning of the powerband as you exit a turn. This isn't always perfect for every turn, but you also don't want to exit a turn at really high rpm, where you'll instantly bounce off the rev limiter.

It's often hard to know what's right for a few reasons:

1: while there's some basic principles, there's more than one way to skin a cat (aka: there's more than 1 "right" way)

2: It's very difficult to teach someone via a message board

3: It's almost impossible, on an internet message board, to really know who you should be getting advice from.


So take all this advice cum-grano-salis.


Here's how I heal-toe rev match on track: (I overlayed a foot cam in the video so you can see my feet)

[ame="http://vimeo.com/70389681"]Spokane 2013, ITA Race on Saturday on Vimeo[/ame]

And you'll notice... I skip gears (always at this track but not always at others). Your brakes do the braking, not your clutch/tranny. Also, every time you're having to blip the throttle under threshold braking you risk a misplaced revmatch throttle blip that will upset your braking causing you to lock up or opposite; unnecessarily elongate your braking zone. Both are very bad if following a competitor closely into a corner.

There's one track locally where I go into turn 2 and shift from 5th to 3rd but then we go down a steep hill in 4th (90mph) into a 2nd gear corner. In that down hill brake zone, for some unknown reason (I've examined the data), the car just feels better when not skipping gears. However, even then (like in last weekend's race there) I will occasionally over rev the engine during the "blip" and as a consequence have to either push on the pedal harder to compensate or alter my braking line.

Ok, that's about all the info I can get across on a message board. Good luck, have fun at the track and be safe. Remember, enter the corner in the gear that you're going to leave the corner.

I wish I could see these videos at work. SUBSCRIBED.

My FR-S should be arriving mid-August or so, and I should be arriving home late November to meet it. I'm very excited to start learning to heel-toe. I miss the experience of learning to drive a manual, so it's kind of like getting a second chance.

Like when you've seen a really good movie, one that you would/have watched multiple times, and are jealous of the people who haven't seen it because they still get to see it for the first time.

Hey Mike,

Can you elaborate on this because it's been my experience that the opposite is true. I've rebuilt several transmissions (albeit FWD and just recently in the paddock at the race track) but at looking at the operation of the various forks, collars and rods; I cannot see how skipping gears increases synchro wear. If you're skipping from 5th to 3rd then your not putting wear on the 4 gear synchro on that corner, lap after lap after lap. To me, that reduces wear. It looks like what you're advocating is trading 4th gear synchro wear in exchange for 3rd gear synchro wear.

Now where I would recommend what you suggest is in the instance where the 3rd gear in your transmission is going bad, it "crunches" on the downshift and you don't know how to double clutch while heel-toeing. With a bad 3rd gear synchro, you can down shift from 5th to 3rd and row through 4th with the clutch still depressed which will aid in slowing the main/counter shafts allowing for the collar to slide over 3rd gear more easily without a "crunch". But doing this is trading 3rd gear synchro wear for 4th gear synchro wear. It's kind of a moot point anyway though because the revmatch downshift to the 3rd gear synchro isn't anywhere near as stressful as the upshift from 2nd to 3rd is when you're doing so at redline. At this point, it's all just 6 of one and half a dozen of the other I suppose.

First off, lets return to the basics. This is what a (simplified) drivetrain looks like:

Engine <-> Clutch <-> Midshaft <-> Transmission <-> wheels

Effectively, it is the clutch's job to connect the engine to the midshaft, and the transmission's job to connect the midshaft to the wheels. The clutch is engaged/disengaged via clutch pedal, and the transmission engaged/disengaged to connect the midshaft to the wheels at different ratios.

The clutch can "slip" to make up for differences between the engine and midshaft rotation speeds during the engagement process. Likewise, the synchros on the transmission will "slip" (technically incorrect, but same purpose) to bring the midshaft rotation speeds in line with the wheels at the ratio of the gear selected.

Now, for example's sake, lets say you're going 70 mph, in 5th gear, and this is roughly 4000 RPM. In 4th gear, this would be roughly 4800 RPM, and in 3rd gear, roughly 6200 RPM. When the transmission and clutch are both disengaged, the midshaft, momentarily, is spinning at the same RPM as the engine. Friction will slowly bring this speed down, but for the purposes of our example, lets assume there is no friction. If you're downshifting from 5th to 4th at 70 MPH, then the 4th gear synchro is bringing the midshaft up to 4800 RPM so that the gear can engage as you go into the gate, a load of 800 RPM. If you go from 5th to 3rd, then the 3rd gear synchro needs to bring the midshaft from 4000 RPM to 6200 RPM, a load of 2200 RPM. However, if you go into the gates sequentially, then going from 4th to third at 70MPH reduces the load to 1400 RPM.

Not only are you splitting the RPM load between the synchros over two gears, when you factor in the speed of gear engagement, you're also effectively doubling the amount of time being allowed for the RPM changes to happen. The amount of time being allowed for a synchro to do its work also affects wear. If you gently hold the shifter against the gate of a gear, it'll eventually "slip in" effortlessly when the synchro has brought the midshaft up or down to the appropriate speed of the gear. Conversely, if you shift very quickly, you'll need a lot of effort to get into the gear. This is why it's very difficult to get into 1st gear when you're doing 60MPH. Can you do it? Yes, but the load on the synchro is so large that it takes a while for the midshaft to speed up to the appropriate RPM, even if you push HARD.

Please let me know if I need to clarify anything here; I'm typing this train of thought while constantly getting inturrupted at work.


*note* the total amount of work being done by the synchros is the same. The key here is splitting the load, and allowing the work to be done over a larger period of time.

Edit: Things in this post by myself are factually inaccurate because transmissions are little more than black magic and created by elves in dark places from far away lands. I have corrected the oversights in the later post.


The gears spin freely via needle bearings on the main-shaft they are only being rotated via their corresponding gear on the counter-shaft until they've been locked to the shaft via the shift collar. This is semantics but the distinction is clear: The synchro does not bring the input or output shaft into speed with the gear. The synchro brings the gear into speed with the shaft.


That would make sense if what we were doing was synchronizing the shaft speed but we're not, we're synchronizing the gear speed in relation to the shaft.

For sake of argument, lets assume a 5 gear is a 1:1 ratio. This way we know that the input shaft and output shaft at 4000rpms are both spinning at 4000 rpms and we will use 70mph for this. Now if I want to change down to 3rd gear while maintaining 70mph our output shaft will remain at 4000rpms (70mph) and in our "frictionless vacuum", with the clutch depressed the input shaft (shaft that goes into clutch) remains free spinning at 4000rpms. When we shift from 5th to 4th we are matching the gear to that shaft speed not the other way around so now we have engaged 4th to the shaft via the synchro and since all we did was change the speed of the gear (and not the shaft) that means the shaft is still spinning at 4000rpms when we select 3rd and the synchro will have to do the same work regardless of whether or not we went from 5th to 3rd or 5th-4th-3rd in the same clutch depression.

So all we have achieved by using the 4th gear gate in between 5th and 3rd is a slowing of our shift which gives the gearset time to slow down (by a fraction of a second) in the oil which negligibly reduces any wear on the 3rd gear synchro but yet puts unecessary wear on the 4th gear synchro and to absolutely no benefit in lap time.

So I guess I stand by my argument that using the 4th gear "gate" while the clutch is still depressed while going from 5th to 3rd does little to nothing to reduce the wear on 3rd and only adds wear to 4th unnecessarily.

Thank you for the polite discussion as always. Your turn. :D

Non-related to the debate Mike and I are having..


Heel-Toe-Double-Clutch

This is my 72 year old dad in my race car:
[ame="http://vimeo.com/70975448"]heeltoedoubleclutch on Vimeo[/ame]

We'll agree to disagree... because I know we can go on forever.

Strong anecdotal evidence the skip shifting causes premature failure, based on my S2k experience, however.

Woodwork from S2ki. This post is 12 years old!

NO WE WON'T! Someone here is wrong! :(


.....and it's me (sort of). So I will eat crow.

Yup, the gears on the mainshaft (input) spin with it. You were right about that. The gears do ride on the shaft with needle bearings but because of the counter shaft they spin in relation to the mainshaft so slowing the gear, is slowing the shaft.

Thank you for the correction.


Now, woodwork. Let's address that. Woodwork is specifically talking about upshift and even skipping gears during the upshift. Why? Because downshifting isn't done when the engine is at redline, the engine speed is always lower when downshifting under braking, the synchro is doing exponentially less work. The upshifts are the primary wear feature on the synchros.

However, I do concede that a row through 4th (with clutch still depressed) before snagging 3rd will transfer some wear away from 3rd and onto 4th and that you are right. I still maintain that the wear savings is negligible in this regard though.


I still won't do it.

A) Well because I have triple cone synchros on my 3rd gear and not on my 4th!
B) I want my right hand spending the least amount of time off the steering wheel as possible when threshold braking at 130mph. Doing the extra "row" just isn't worth it.
C) The more time you spend whipping your shifter about puts more wear on aluminum runners on shift forks.. once these wear out, it's a lot more expensive than some brass synchros. (also see: don't rest your hand on the shifter)
D) All of this is moot if you can heel-toe-double-clutch, then you have no wear on downshifts, skipping or not. Heck, you'd be able to downshift with no synchros at all.
E) It's too slow and for God's sake, I'm racing over here!


Oh yeah, and I just like to argue with you Mike. :D

I need to practice my heel-toe-double-clutching...

On a side note, I thought I broke my trans on the s2k. Turns out my clutch disk failed. Not wore out, but failed. Waiting on pics to see how much clutch disk I have left after 115k miles of mostly track, canyon, and bumper to bumper traffic.

Does that mean you'll be up and running sooner? :D!

Not particularly, since I had found a tranny to frankenstein with mine, but now I need to buy a clutch disk and bearings -_-

Awww. Maybe you can take Allan's. Hahahahaha. Good luck, though.

GPW > BB

Although his car has some really, really nice parts... :wub: I'm curious how his Ohlins will do if I dial them in. I may have to offer to dial them in in exchange for co-driving a day...

Very good animation of what Mike and I were on about.

[ame="http://www.youtube.com/watch?v=HE17WUepkKA"]Transmission Animation - YouTube[/ame]

I did that on my STi. Thought the trans went (which would be insane because the STi 6MT is bomb proof) Found out it was the clutch, which I had thought I wore out but instead I pulled it and one of the brackets holding the springs in the center of the disk fell out in 3 pieces. Clutch still had plenty of life left, but was shot.

Splines rounded off, so it was just spinning freely (somewhat).

https://sphotos-b.xx.fbcdn.net/hphot...38916892_n.jpg

This is impressive!! Is there a benefit in doing this at the track? I double clutch rev match on the street, but since I'm going at a slow pace there is no need to include a heel-toe blip. I do a traditional heel-toe at the track. I never saw a heel-toe double clutch done. Pretty cool!!

Edit: Just realized I don't double clutch on the street. I just rev match with no brakes.

If you didn't have synchros you'd be upshifting much slower and you wouldn't be able to downshift without a double clutch, or at least it'd be extremely difficult. So yes, double clutching during a downshift decreases the wear on synchros (wear from downshifting) by a spectacular margin.

I upshift very slowly on the street and double clutch on my down shifts. However, on a race track I simply heel-toe. I have yet to be able to heel-toe-double-clutch at race pace without giving up time or control. During practice sessions and test days I will try it a few times but come the race... I do what is fastest and in most control. On the race car I don't care if I have to rebuilt the tranny every other year. On the street car I expect the transmission to last more than 200k.

In the discussion about whether it is best to skip gears or not when downshifting, there is one other thing not mentioned (or I just missed it!) If you need to go down more than one gear, you will need to wait until near the end of your braking to do the heel/toe, regardless if you double clutch or not. This is because doing it too early will over-rev the engine, possibly causing the rear wheels to overslow (will seem like they are locked, but maybe just spinning slower than the car is going,) and a possible spin or engine damage can occur. Just ask the air cooled 911 guys what the bill is for making this mistake. Those engines REALLY don't like to be over-revved.

I will actually engage every gear in sequence as I shift, no skip shifts for me on the track. Having been track driving since the mid-80's, including many endurance races where accuracy and gentleness trumps raw speed, I'm prety smooth and don't seem to wear out transmissions or clutches, but it took me a while to get there. There was a time when I was really sloppy and wound up with some twisted metal in my early driving days.

I find that not skipping gears helps my timing of when to shift, so I don't shift early or into a gear that I am not going slow enough for. On the street, I will skip shift, but I double clutch if I do.

There is a lot of debate on this topic on many different forums. I think there is no absolute right answer, you just have to figure out what works for you.

Mike

My 2 cents, work your way up to being able to heel-toe or blip-shift efficiently on track at all times...but begin your practice in the street where there is less consequence. It takes countless hours to hone this skill so don't rush through it and unnecessarily stress your transmission.

?? There is more consequences on the street to get into an accident & putting others at risk. In addition, it's harder to do a heel-toe when you are not threshold braking. Unless you drive like a tool on the street.

Uh.. on track I'm doing triple digits, on the street I can practice at 30mph and am under no obligation to do while in traffic (no cars around). Learning heel-toe on track is less safe.

Ross Bentley agrees.