Porsche Club AutoX - Saturday, Aug 30th

Hi Rich!

Thanks for jumping in. I was going from a combo of an
obviously foggy memory when you drove a different time
with me in the car and then some theories.

I forget how long it takes to cut the fuel in my car
if you are braking. Didn't seem that long when I tried
it. I trailbrake a lot but then again, I'm also used
to longer turns at a racetrack right now so my sense
of timing is probably biased towards that, and not the
shorter turns in autox.

Patrick, keep us posted on what you do. I'm always
curious.

Cheers,
Allan

Rich Sandor wrote: I was doing it in the Fiero. I LFB in any car that I'm racing.

You're smooth Rich, very smooth... I didn't even notice.  Of course, when you were piloting the Fiero while we were testing the course, it's no surprise that I wasn't staring into the driver's side footwell. I was more interested in where we were headed.

I'm curious about trying out this left foot braking now. I'll see whether an old dog can learn a new trick.

 

Rich Sandor wrote: The hardest part for me was remembering to go back to normal braking when entering the stop box. Otherwise your left foot is committed to the brakes and there's no way to clutch in... = stall!

...

Hey Rich, welcome to our little corner of the automotive universe.

I don't recall seeing you doing the left foot braking when driving my Fiero during course setup/testing. Were you doing it, and I simply missed it, or is left foot braking something you only do in cars you're familar with?

Edited by Patrick

Gary commented that Rich seems to plays tricks with his feet while driving the course. He uses his left foot to brake so as to reserve his right foot for GO duty. Is there some value to learning this technique, or is there a danger of over-complicating things?

The hardest part for me was remembering to go back to
normal braking when entering the stop box. Otherwise
your left foot is committed to the brakes and there's
no way to clutch in... = stall!

It takes time to learn, for sure, and for ME, it is
faster. However I have seen data for GT drivers in the
same car, getting the same times with and without
LFB.. however I'm not sure either was going as fast as
humanly possible. The advantage is multiplied on a
course with more corners (like autox) and not as
noticeable on a course with few corners. However, I
still think LFB has the potential to be faster.

It's undeniably advantageous on older cars with big
turbo lag..

I mostly wanted to weigh in because on the previous
autocross I was bitching about Gary's 9146
understeering, but I didn't have the problem this time
around. I noticed Al mention that perhaps I wasn't
trail-braking.. the thing I realized is that I *was*
trail-braking, but I was starting too late and
carrying too much speed.. the car just wouldn't turn
in.

This time I was braking earlier and smoother and that
let me carry more momentum into the corners.

There is a way to have you do a sweeper over and over
again, but it'll cost you a lot of money to book the
track.

I do have about 20 cones....

Re: left foot braking: IMHO, don't bother. It's a skill
that takes a long time to learn properly. Over the years
of driving you have done, you have developed a super
sensitive touch to your right foot when on the gas and
brakes. Your left foot just goes in/out on the clutch.
The time it takes to develop a sensitive left foot can be
quite long.

Some modern cars like mine (2004), don't respond well to
left foot braking. You can go on the brakes for about a
second or two before the fuel is cut off. So trying to
use both pedals for any length of time won't work on a
newer car.

Kids who grow up racing carts learn left foot braking at
a young age and can carry that skill to race cars and do
extremely well. They will be faster than an old fart like
me or you. So I don't know. I haven't bothered to
learn it but thinking about it more, you may want to play
with it if you're curious. Try it when you drive to work,
but with nobody close behind you. lol!

That pro autox guy I mentioned a while back said that if
an experienced autox driver tried to learn left foot
braking, expect to be slow for a full year before seeing
any benefit. This is also with a much longer racing
season that you are currently running now (and tons of
practice on the street).

Yes, getting alignments can be costly. Make some
decisions and get it sorted, man!

karnak wrote: ...when it was {Rich's} turn, he performed maneuvers with the car I did not seem were do-able. by the end of the day, I had applied some bits here and there. he drove it well.

Rich is a great driver. He has great balance when it
comes to drifting too. I suck by comparison. lol!

karnak wrote: ...(and if you are still reading this and it does not sound like Bla, Bla, Bla.. then please consider coming to the next event. all these words can be boiled down to some simple things that will help anybody drive more soundly) it is fun stuff!

Indeed! The other key benefit is that the average
speed of autocross is about 60km/h so the car control
skills you learn here are directly applicable to city
street driving. Skills you learn here can save your
bacon!

karnak wrote: Here are a couple more links to some runs but please turn down your speakers... https://www.youtube.com/watch? v=e9awv5Ww2lchttps://www.youtube.com/watch?v=9Le1Fjb-ofQ

Cool!

My ears are bleeding and I feel sea-sick, but cool!

Here are a couple more links to some runs but please turn down your speakers...

https://www.youtube.com/watch?v=e9awv5Ww2lc

https://www.youtube.com/watch?v=9Le1Fjb-ofQ

Hey Patrick,

I know you want to learn so that's why the peanut gallery
spoke up. :) Kudos to you.

As my video in the post above showed, a simple lift when
you have plenty of steering wheel input is all you need
to spin. This is what you did. A lift moves the weight
transfer to the front, unloading the rear tires a bit and
then they can come loose.

That's why you want to get most of your turning done
before the apex of the turn so at the apex you are
unwinding the wheel (reducing steering demands) while
getting on the gas. Getting on the gas moves the weight
transfer to the rear, giving you more grip at the rear.
This also reduces the weight at the front, giving you
less grip up front. Good thing you are unwinding the
wheel then. Think of when you don't do this.....what
happens? Think of "understeer"; that horrible shuddering
or plowing coming out of a turn where you want to get
down the straight and are on the gas a bit but your car
isn't turning and you mow down some cones at the exit of
the sweeper.

To help control the understeer or oversteering traits of
your car in a turn, you need to fully understand these
issues. So in the case of your spin in that tight
sweeper, you had more turning to do at the start of the
spin (you didn't want to hit that cone at the exit) - so
you didn't have enough grip at the rear for that speed
and the spin showed you had plenty of grip up front (car
"oversteered"; steered too much!). The ideal line there
was to get slowed down a bit more at turn entry and get
the car rotated more during entry so you could accelerate
out of the turn. You simply carried too much speed into
the turn and lifted or coasted through the turn while
feeding in a ton of steering. The combo was too much for
your tires.

For tire pressures, you need to play with them. Generally
speaking, higher pressures are required for heavier cars,
but IIRC I ran 34psi at the rears of my car and it's
several hundred pounds heavier than yours. Factory wanted
39psi for the rear of my car for street. That wasn't
where the grip was at autox. The race track is different
and I run 38psi there with the tires I use.

Try dropping the rear pressure a few lbs.

The ideal method is to align your car and tune the tire
pressure so the temperatures are equal left/centre/right
on the tire tread under hard cornering. This shows the
tire tread on the outside tires are flat on the asphalt
in a hard corner. You need a pyrometer for this and a
helper to take the temps immediately after loading the
tires and getting them hot. I have a pyrometer.

You might be better served with a slightly stiffer front
suspension, but be careful here. A novice mistake is to
think stiffer is better. Body roll is fine, as long as it
isn't hindering your cornering. If you are hitting the
suspension bump stops in a turn, that's bad. Mild roll is
fine, and good for the undulating pavement at the
skidpad. Especially for the street and a racetrack like
ORP. Too stiff and you'll be demanding a ton from your
tires and will "skip" across undulations in the pavement,
and this lack of grip isn't good.

When I was at ORP last time, it was really hot and my
grip in the morning sucked. So I softened the shocks and
the grip went up a lot and I eventually set a new
personal best lap time. Remember what I did; I softened
the suspension!

Gary is right though. Do one thing at a time so you can
better learn how these changes affect the car. I can type
and type and type, but if you are anything like me then
you will learn best by living it rather than reading it.
Keep what I'm saying in the back of your mind and next
time you're out there, pay close attention to the car and
what it's doing, early in the day. Really learn what it's
doing. Cause and Effect kinda thing.

Cheers,
Allan

karnak wrote: i like your videos Patrick. i may take one of mine and attempt to filter the sound a bit to see if they will show my line on one of my faster runs. my bracket is a bit shaky also..

I'm seriously considering buying a remote audio recorder, such as can be seen discussed HERE.

If I get one, I plan to construct a bracket to mount by the rear license plate to hold the recorder in during autocross. I have found in the past (using those cheap little eBay thumb-sized cameras) that audio recorded back there is perfect. The sound of the engine/exhaust and squealing tires comes through loud and clear with NO wind noise. It's... beautiful.  An example from the video vault is HERE.

It's a relatively simple matter during the editing process to match up the recorded audio file to the appropriate video file. So that frees up where the camera can be mounted big time, as wind noise would no longer be an issue. Hallelujah!