napaul

i apologize in advance but i am curious what is this heel toe thing that you guys speak of? i have had a fairly sheltered life when it comes to driving just drive a chevy pick up and a kia with my wife and kids around and pull out my yamaha vmax for a shot of speed when needed....is this some racing maneuver?

Idiot964Owner

http://www.edmunds.com/how-to/heel-a...downshift.html

Bertrand

The edmunds' described procedure is incomplete. The heel and toe I know is:

1- In gear X, brake
2- Declutch an put in neutral (While braking)
3- Clutch in neutral (While braking)
4- Blip the throttle in neutral with the heel (While braking)
5- Declutch and put in gear X-1, X-2 or X-3 (While braking)
6- Clutch in.

That way you get ALL the drivetrain at the correct speed, ready for the last clutch-in.

I don't do it much with the 964, but I HAD to do it in my younger days.
Going down the Alpe d'huez hairpins with 4 drum brakes, I definitely needed the 3 to 1.

jamest

The Edmunds described technique relies on the synchromesh to match engine and gearbox speeds . Yours uses a double de-clutch technique to do the same thing. I think it is pretty rare to see people double de-clutching on a modern car although it is certainly kinder on the synchro (providing you are matching speeds accurately).

Here is the late Mr Senna demonstrating how to heel and toe in a pair of loafers:

http://www.youtube.com/watch?v=8By2AEsGAhU

boxsey911

I've never seen anyone jabbing the throttle like that in the corners! Amazing to see the sort of things that a driving genius did, that would never be considered by most of us.

OT...I'm looking forward to the Senna movie this summer:

http://www.youtube.com/watch?v=JOzq927y15o

John Boggiano

I double-declutch and heel & toe pretty much all the time. I've done it so long it feels weird not to.

I remember once looking at some telemetry comparing Prost's and Senna's technique on the same track. Senna's had this very characteristic of constantly jab, jab, jabbing at the throttle, continually probing the grip, pushing for just a tiny increment whenever there was one to be had.

Bertrand

The two techniques:
http://www.youtube.com/watch?v=IuoZeuSgEj4

James, you are right.
It was my father(!) who taught me to put in neutral to preserve the synchros.

Still, from experience, the blip in neutral really helps to slot the first gear in from 3d or 4th.

jamest

Bertrand - I agree, you can achieve a much smoother change than relying on the synchro. I don't use double de-clutch with heel and toe on track because, for me, it is one too many things to think about getting right on the approach to a corner.

Boxsey - I can't wait for the film either, I just hope the quality of it does the great man justice.

There are lots of theories on why Senna used to pump the throttle, I agree with John that he was feeling for and exploiting the available grip but some think he learned it during the turbo era to reduce turbo lag when exiting the corner.

elbeee964

H&T may soon be relegated to such old technology quaintness as coaxing a cold day carbureted engine to start.
But it's still fun to do.

I admire Senna's abilities.
And admire Prost.

Makmov

Watch the V8 Supercar guys. There are quite a few that drive like that. The other half are left foot brakers.

Schumacher was much more smooth on the throttle.

Makmov

like the other said, why you do it nobody mentioned yet, so mentioning that might be helpful as well.

It was a way of getting the most of out the car. If you didn't heal-toe in a corner you would crash!

You need to match the engine rpm with the transmission to get a smooth down shift. If you just let the transmission drag it's rpms down you would spin in a corner because the rear tires would break loose.

Bertrand

So if I may sum it up, it is, with synchroed cars, a racing technique aimed at maximizing deceleration.
It is useless with a 964 on open roads.

Except, as John said that it's fun and oh... THAT sound.
(You can hear it in 'Le Mans', when the 917 and the 512 brake side by side at Arnage at the end.)

KaiB

So if I may sum it up, it is, with synchroed cars, a racing technique aimed at maximizing deceleration.
If I may, no, not really. It is a technique necessary to maximize smoothness (to maintain balance) while selecting the proper gear for exit. It should be used under all conditions, practiced at all times and become second nature. Brakes slow cars down without help from engines these days.

OT ... I've never seen Senna's foot work the throttle, absolutely amazing.

John Boggiano

What he said.

All about smoothness, mechanical sympathy, involvement with the car, enhanced driving pleasure.

Makmov

I think he means Symphony

this is a pretty good discription. It is a technique necessary to maximize smoothness (to maintain balance) while selecting the proper gear for exit.

and there might not be a hard car to do it in than a 911