Zero10

I ALWAYS double clutch, I was told it is too hard on the syncro's to just push it into a lower gear entering a corner. I usually take it to neutral, then stab the gas, push the clutch, and it goes in gear really nice, and since your revs are already close, I usually let the clutch back out right away.

I was told this was the right way, was I taught wrong?

Z-man

Double clutching (actually double de-clutching), is a good thing to do. It helps to line up the syncros in the tranny. You don't really need to blip the throttle when you let the clutch out the first time, just blip it a little just before you engage the clutch (with 3rd engaged), like you would in a heel-and-toe downshift.

-Z.

ERAU-944

i always used just the brakes to slow down before i learned how to heel and toe. my thinking was it is MUCH easier(and cheaper!) to replace brake pads than it is to replace the clutch. now i downshift, makes driving around town much smoother, and still little wear on the clutch, because the brakes are doing just that - braking!

-Michael-

FSAEracer03

Well Z-Man, I hate to tell YOU this, but after working at a race shop for a couple years, going to the track with customers and coworkers, and learning a thing or two... yeah it is. If you run across a post under the racing section about left foot braking, you can see what I learned about downshifting from people at work. As for people babying their car, yeah, you can wait longer to downshift and only use the brakes, if you do it earlier, your using the brakes AND the engine to slow you down. It's still seamless to the passenger... it all depends on preference really, but many people use it.

-Kevin

FSAEracer03

Double clutching, ot double declutching for all you Brits, was started way back when before synchromesh was used in trannys. When you downshift and place the shifter from say 4th to 3rd, these little brass thingys called synchros line up the gear speeds for ya (some race cars use carbon synchros, street cars use brass ones)... and without them, you have to double clutch. If you don't the gears grind. Now as any of you with failed transmissions will know, when your synchros blow, you have to either double clutch it old-school style or rev match for upshifts even though you are using the clutch ...that's how my S10 is currently until I go back home and drop in my spare tranny on my gravel driveway fun fun!

-Kevin

FSAEracer03

lol... well I see i just basically double posted what Z-man did... I really should read all pages of posts before replying!... ehh, well I'll learn someday

jeeper31

Are you saying?

In 4th gear
in with clutch
put car in neutral
out with clutch
(no gas blip here)
in with clutch again
put if 3rd
blip gas
out with clutch

dgz924s

Dog Box tranny is a good example of a tranny needing to double clutch. Most old school race trannies need the extra pedal work. Dal

Z-man

First off, let's not add left-foot braking into the mix! However, it is a very helpful technique for them turbo boyz: allows them to slow down for a corner, while appling throttle and thus keeping BOOST up. Hehehe...

Second: the heel/toe downshift should occur after MOST of the braking has been done with the brakes. Why? If timed perfect, the driver has completed both his braking and his downshift at the same time, which should occur the moment before turn in. If the downshift is done too early, then what? You either coast until the turn in, which slows you down, or you apply throttle, but why would you apply throttle when you're still on the brakes?

But more importantly, it is far easier to be consistent when using only one means to brake. If I introduce the tranny as a means to slow down, now you have two factors that effect your braking: two factors make it more difficult to be consistent. Also: by shifting at the end of the braking zone, the whole process can be done smoother. Smoother is better.

Oh, and let's not get into trail braking yet either!

All the performance driving books explain it this way. (Vic Elford, Bob Bondurant, Skip Barber, Ross Bentley...etc).

jeeper31: Yep: that's right.

Interesting discussion.
-Z-man.

jsonnen

Anyone have any idea as to why his car shudders? I don't think it should shudder regardless of his downshifting technique.......

Techno Duck

I dont have a manual transmission 924S (but a manual old school Mustang). The Mustang always needs to be doube-clutched or 8 times out of 10 the gear will grind. Especially when going in reverse. I was wondering..dont you guys find it hard to heel-toe with the pedals on our cars? I mean my friend taught me the basics of doing it on his '02 Nissan SE-R. The gas pedal isnt floor mounted, and i found it very easy to just rotate my heel onto the gas. From sitting in my car, i feel it would be much harder to do that on a floor mounted pedal. Maybe if you were to use the heel for braking and the toes for the gas.

I would think you can get a wider gas pedal, or atleast something with a wide area just towards the bottom of the pedal.

tifosiman

It could be the clutch. I have a centerforce (spring-centered) clutch in mine that does the same thing (somewhat) if someone is brain-dead and does not match revs while downshifting. It is more prevelant on the spring centered clutches compared to the rubber centered ones, from what I have noticed.

Legoland951

You guys are making this too complicated. Here is the simple version:

1. Slowing with brake - wears out brake pads (cost $40) and rotors.

2. Slowing with engine - wears pistons, rings, cylinder bores, cam, lifter, belts, torque tube, transmission, CLUTCH, and just about every moving mechanical part of the car.

Take your pick.

RedlineMan

I'm with you , Legoland;

Brakes is for slowing, clutches is for shifting. Besides, at the rate your brakes should be slowing you, the engine will add little if any resistance... unless you back out of it 500yds before the turn like Z-man!!

Try this link to my Pilot Emeritus Series for another discussion of Heel & Toe (and a lot MORE!):
http://redlinerennsport.homestead.co...18HeelToe.html

If the car is wiggiling and wobbling when a lower gear is engauged and the engine braking is at a high level, I would suspect lousy rev matching for starters, and then worn or broken motor mounts at the extreme!!

Z-man

NICE!

Have you been talking to my so-called "track buddies?" Or the guys with GTC-Motorsports? Or is this from personal experience?!? I have gotten better this year, ya know....

Geez, I get no track respect whatsoever......

But hey, at least I know the theories: isn't that good for anything?

-Zoltan.