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RE: Sad reactions to S4 drive

Peter Berrevoets writes:

> For spirited street driving - and directed towards Avrams "two stage
> lag" and "too much... too little" power on acceleration comments 
> - heel and toe shifting is not applicable

Why not?  I heel-and-toe virtually every downshift, on street or track,
whether the driving is "spirited" or not.  

In particular, I found this to be a *very* effective technique on
turbocharged cars, for the reasons Phil says (for me, I used to keep all
three pedals about halfway down, and then when releasing the clutch
fully the turbo was completely spooled up).

(It's also a very effective technique on naturally-aspirated cars,
especially older Italian sports cars with weak second-gear synchros,
which is probably why my feet are programmed to do this without me
having to remember to do it on purpose...)

Of course, as an answer to Avram's original questions, heel-and-toe DOES
have only limited application.  H&T works when you are selecting a lower
gear for exiting a corner, downshifting to (say) second gear so that
when you start the corner-exit phase you'll be in the fat part of the
powerband.  H&T isn't going to help in most straight-line acceleration
circumstances (who was it who said "please explain how pressing the
brake will help me while accelerating"? :-).  For drag-racing or
acceleration runs, the term "speed-shifting" means not lifting your foot
off the accelerator while you clutch, shift, and release the clutch
pedal.  I've been led to believe it's hard on the machinery, however, so
it may or may not be something you want to do all the time when you get
your new S4, Avram.

Where heel and toe *does* buy you something in straightline acceleration
is from the standing start.  That is, I once -- ah -- decided that the
car next to me at a light would look much better behind me than in front
of me (what can I say except there's a reason that insurance rates for
males under 30 are so high :-).  As the opposing light was turning
yellow, I held the brake about halfway down with the ball of my foot,
raised the RPM level to about 4000 or so with my right little toe, and
then lifted the clutch about a third of the way -- enough so that the
boost gauge went very positive.  When the light changed, I had a bit of
wheelspin (this was a 2wd turbo only, and not even an Audi, I'm afraid)
and when the NCTs hooked up, the car shot off with none of the
wait-two-three-VROOM that normally accompanied goosing the turbo.  Of
course, this is probably even more damaging to the car's internals than
speed-shifting... but I was right, the other car *did* look good behind
me. :-)

Heel and toe is also not something that will help if you're just sort of
puttering along in 5th gear at 2200 RPM and that yahoo in the 5.0
Mustang next to you wants to pass you and you decide you don't want him
to.  And if that's the kind of driving you had in mind, Peter -- in-gear
roll-ons at highway speeds or below -- then you're correct, H&T doesn't
enter into the equation at all.  I guess that when I read the phrase
"spirited street driving," I tend to think of twisty mountain roads, or
at least interesting on/off ramp exchanges, where you're moving up and
down the gearbox often enough that H&T is an integral part of driving

Now, if you and the Mustang are both braking for the same offramp, using
H&T to downshift with all three pedals about halfway down as you're
selecting the lower gear will help ensure that your turbines are spooled
up and you can get *instant* response when you roll off the brake,
sidestep the clutch, and mash the go-pedal.  The way the car rockets out
of the corner when you do it this way is *very* spirited indeed.

In short: if you're going to be braking and downshifting anyway, H&T is
your friend, in any car but especially in turbo cars.  If you're not...
well, we all know what there's no substitute for.  Just take some solace
in being able to catch him once you spool up and pass him at the
offramp. :-)

--Scott Fisher