Miata Mailing List: August 1994, Message #104
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   From: dquara@encore.com (Doug Quara)
Subject: smooth shifting (was Re: Kansei Returns, etc.)
   Date: Thu, 4 Aug 1994 10:19:14 -0400

"Alice T. Liu", On Aug 4,  1:37am, writes:
> Subject: Kansei Returns, etc.
>         
> I take highway 9 every morning to work, from Felton to Santa Cruz.
> It *is* fun.  It's probably one of the tamer streches of the highway.

A few years ago, when I was an active member of the autocross list,
I attended Uniforum in SF.  We got a bunch of us from the autox list
and the Bay Area together and headed up to the White Cockade, a
British pub on Hwy 9.  (Don't ask me exactly where; I don't really know!
;-)

Hwy 9 was an absolute blast.  We had a train of about 9 cars, I think
all of them the locals' autocross cars, with some of them even wearing
autocross rubber.  I drove with Josh Sirota in his two seat MR2, and
my wife Tammy got to ride in a Supra.  In the back seat.  At night,
where she couldn't really tell which way the roller coaster went.
We flew for the 40 minutes in the mountains, the climax of which was
dinner at the White Cockade.  Tammy ended up almost getting sick from
the very aggressive drive in the mountains.  Since I was in a two seat
(and drove on the way back, thanks, Josh), I wasn't afflicted.  But
what a great road, great time, and great people (the ales and bangers
and mash weren't too bad, either! :-)

> But I'm a newbie - I had only about 5 hours worth of experience 
> driving stick before I got my Miata!  I'm sure I am not yet taking 
> full advantage of the road.  My shifting is much smoother now, but 
> I'm still unsure about when I should be down shifting, so if anyone 
> has any tips, send them my way.  For smooth shifting, for instance, 
> from 4th to 3rd, it seems I should be going 30 mph.  Any higher than 
> that and the rev sound gets higher and the car lurches a little.  
> 

There have been a few replies on the list about techniques, and they
were legitimate.  Maybe we should address the proper techniques in
"normal" driving (ok, normal for most people, not those of us who
can't seem to take it easy in our fun-fun-fun Miatas).

Heel and toe downshifts aren't necessary for the uninitiated.  It
isn't necessary in normal driving to hit the latest braking point
for a turn.  In street driving, it is OK to trail the throttle
(simply coast, not being on the gas or the brake), push in the clutch,
blip the throttle, downshift and let out the clutch matching the RPM
to the next gear down.  THEN go to the brake.  I rev-match EVERY
SINGLE shift in my cars.  I only heel-toe when I'm driving aggressively.
In fact, it's very difficult to heel-toe when not pushing it; the
brake pedal is not down far enough for convenient contortion of the
ankle.  

After a sufficient time and acclimation to the gear spacing, which
speed in which gear, etc., is it appropriate to start a technique as
heel-toe.

I will echo what others have said.  In Alice's example, 4-3 at 30 MPH
is a bit slow, but that's where idle speed for 3rd gear matches
the speed.  By blipping the throttle during the clutch/declutch,
downshifts at higher speeds can be accomplished.  The motor in the
Miata will take 7000 RPM (not every shift, of course, unless you
don't mind wearing it out before its time.  I know I'll hear from
those who have really flogged their motors for 200,000 miles driving
it flat-out all the time with no problems, but I don't feel comfortable
doing it!)  Experimentation is required.  Remember, that the difference 
of engine speed compared to tranny speed (car speed) and using the clutch
to force the engine to match the tranny speed is what causes all the
clutch wear.  Match RPMs and the clutch is a redundant device.  I've
already been able to change up and down with and without heel and toe
without ever moving my left foot from the dead pedal, and I've only
had the car three weeks.  

> The real test is when I have to drive the hills in San Francisco.
> I haven't had a reason to go there since I got my M-edition, but
> the day is coming I'm sure.

This should be relatively easy.  There are a few ways to make this easier.
For smaller hills, with the foot on the brake, simply let out the clutch
until it starts to engage (the tach starts to drop).  For smaller hills,
this should hold the car in place for you to move from the brake to the
throttle.  Then feed in gas and let out the clutch.  NOTE: this should
be done with the least amount of time having the clutch hold the car
on the incline, so as to not prematurely wear it out.

An even better way, for small and large hills, is to use the handbrake.
Feed in throttle with the right foot, work the clutch with the left
foot, and slowly release the handbrake.

Still another way is to heel-toe while on the incline.

All of these take a little practice and are not as intimidating as they
sound.

Welcome to the world of row-it-yourself.  I've owned at least one
manual shift car all my driving career, and I probably always will.  Shifting
seems to keep the driver more involved, more aware, and more alert.

Happy shifting!  (Note my .sig!)  (Sorry for the length of this note).

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