Autocross Videos - Tips and Discussion

[tony_r]

Some 3rd gear action at Crows Landing. All twins belong in STX.

[ame]https://www.youtube.com/watch?v=WBeJUrX0-aA[/ame]

[Simmons]

Originally Posted by Biggins

That looks like a good site, but why did they make the course so tight and slow? I hope the big event there in a few weeks flows better. Nice driving!

I was thinking the same thing......

[cueball89]

Originally Posted by Biggins

That looks like a good site, but why did they make the course so tight and slow? I hope the big event there in a few weeks flows better. Nice driving!

Originally Posted by Simmons

I was thinking the same thing......

I'm not sure why it was designed that way. The large offsets having to get all the way across the runway reminded me of the tour at Devens last year which I sucked at, it was good practice for me.

The start and finish were alongside each other maybe they were trying to keep speeds down in that section?

There is a 2 day event the first week of June before the tour, we'll see what kind of course the CNY region designs. I'm not sure who is designing the course for the tour.

[Simmons]

Originally Posted by cueball89

I'm not sure why it was designed that way. The large offsets having to get all the way across the runway reminded me of the tour at Devens last year which I sucked at, it was good practice for me.

The start and finish were alongside each other maybe they were trying to keep speeds down in that section?

There is a 2 day event the first week of June before the tour, we'll see what kind of course the CNY region designs. I'm not sure who is designing the course for the tour.

Chris Morton is.

[cueball89]

Originally Posted by Simmons

Chris Morton is.

WNY region designed the course from Sunday. I drove a local event course designed by Chris last year, it was a lot of fun.

[Simmons]

Originally Posted by cueball89

WNY region designed the course from Sunday. I drove a local event course designed by Chris last year, it was a lot of fun.

Awesome,...good to hear.

I will be designing the Evo School/ Practice course for the tour.


Simmons

[H1C]

To be clear, I'm not the pro, my friend is. To give a bit of background: he used to pro-am rally back in the 80's and 90's, and used to go to national auto-x events, but does it only for fun locally now. He can consistently pax in the top 5 or 10 in a pretty deep region. And that's on Federals or Nexens, not RE-71s or Rivals. We have a few former national champs here, and several others who have finished in the top 3 - 5 at Nats in their classes multiple years. He also, more than anyone else I know, can hop into a car and extract close to its full potential on his first run.


I've co-driven with him several times in my car over the years, and I had him take a couple of runs this weekend at a PCA event. I think it's finally dawned on me what he does differently from me:


1) He slows early for corners and never stands on the brakes
2) He takes a wide enough arc and turns in early so that he can position for corner exit early
3) He gets very tight on the apex cone
4) He is aggressive on the throttle and stays on it starting at the apex cone. He is essentially making the straights longer. I notice that I wait until it's straighter to get on the gas, and breathe the throttle in a few spots where he stays on it. He is trusting the tires to hold where I chicken out.



Here are videos for comparison.


The pro:
[ame]https://www.youtube.com/watch?v=aC6lPElAGoI[/ame]


The 'okay' autocrosser:
[ame]https://www.youtube.com/watch?v=CaJN39zeaGw[/ame]


Event results:
http://www.peachstatepca.org/Results...oss/05-20-2018


I find it encouraging that my car can raw-time two pretty well driven 991 GT3s. Of course on a more open track, it wouldn't stand a chance.


I found it very funny that my friend kept saying how I need a bigger front sway bar during his run. I find the car plenty stiff, but he thinks I need a bigger bar, stiffer front springs, or both. I have MCS SAs with 500 F 450 R springs, and a TRD front sway.


Anyway, I hope these videos and my observations will help other 'okay' autocrossers out there attack the course better. I welcome observations and comments from other pro-level and okay autocrossers here.

[oinojo]

Originally Posted by H1C

I found it very funny that my friend kept saying how I need a bigger front sway bar during his run. I find the car plenty stiff, but he thinks I need a bigger bar, stiffer front springs, or both. I have MCS SAs with 500 F 450 R springs, and a TRD front sway.


Anyway, I hope these videos and my observations will help other 'okay' autocrossers out there attack the course better. I welcome observations and comments from other pro-level and okay autocrossers here.

Swaybar is important on these cars. You can spring the front pretty stiff but it won't give you the same confidence a proper size swaybar will. The swaybar will give exponential rate as it twists, so it will make the car easier to drive at the limit vs springs. I have found a 22mm Perrin is the best compromise so far in terms of rate for an STX car no matter the spring rate.

[H1C]

Originally Posted by oinojo

Swaybar is important on these cars. You can spring the front pretty stiff but it won't give you the same confidence a proper size swaybar will. The swaybar will give exponential rate as it twists, so it will make the car easier to drive at the limit vs springs. I have found a 22mm Perrin is the best compromise so far in terms of rate for an STX car no matter the spring rate.

That's the one I was thinking of getting at some point. I've tried the 25mm Hotchkis and found it way too stiff. The TRD is just under 21 mm iirc, so I figured the 22 mm would be a good middle ground.



I didn't find it funny because I didn't believe him -- I do think the car would be more settled at the rear with a bigger bar. What I found funny is that he's able to talk while driving so fast!

[Icecreamtruk]

So legit question here. Why does everyone and their mother in autoX wants their car to understeer to hell and back? Wouldnt a car that rotates easier be a lot more enjoyable to drive (and possibly quicker)? Those videos posted there. That car has very much chronic understeer (not once did it do anything other than push, push, push), yet he suggest more front bar and/or stiffer springs? Im not questionning anyone's ability here, I have never autocrossed and im just curious.

[tony_r]

Originally Posted by Icecreamtruk

So legit question here. Why does everyone and their mother in autoX wants their car to understeer to hell and back? Wouldnt a car that rotates easier be a lot more enjoyable to drive (and possibly quicker)? Those videos posted there. That car has very much chronic understeer (not once did it do anything other than push, push, push), yet he suggest more front bar and/or stiffer springs? Im not questionning anyone's ability here, I have never autocrossed and im just curious.

Not sure what you're seeing to indicate massive understeer? The front tires are talking with inputs, and there are some driver induced understeer moments, but the car turns fine.

Pro-guy was complaining about oversteer. You can hear it in his throttle input and see some correction. It's not crazy bad but it's there.

[Icecreamtruk]

Originally Posted by tony_r

Not sure what you're seeing to indicate massive understeer? The front tires are talking with inputs, and there are some driver induced understeer moments, but the car turns fine.

Pro-guy was complaining about oversteer. You can hear it in his throttle input and see some correction. It's not crazy bad but it's there.

I didnt see hear any oversteer, all I saw wasa few cases power over in some corners, and the car pushing hard in the rest of them. I mean, more than half a turn of steering input thru most corners with 0 correction or movement on the rear until he steps on the gas means its an understeery car, that the driver forces to power over with the gas. If the rear would rotate properly under turn-in he would be able to power out of those turns earlier and clear them at higher speed. I dont mean to say that the current setup looks bad or slow, au contraire, but I dont understand the suggestion for a stiffer front, which would make the car slower to me. But like I said, im not an autocrosser and would like someone to explain why a stiffer front in this case would yield a faster car.

[H1C]

Originally Posted by Icecreamtruk

So legit question here. Why does everyone and their mother in autoX wants their car to understeer to hell and back? Wouldnt a car that rotates easier be a lot more enjoyable to drive (and possibly quicker)? Those videos posted there. That car has very much chronic understeer (not once did it do anything other than push, push, push), yet he suggest more front bar and/or stiffer springs? Im not questionning anyone's ability here, I have never autocrossed and im just curious.

Here's how my pro friend has explained it: you don't want a car that rotates too easily when driven under the limit, because at the limit it will be too difficult to control and you will have to correct or lift and scrub speed.


You want a car that is somewhat pushy under the limit, because as you push harder and approach the real limits of the car, it will become more neutral.



Keep in mind that, for him, pushing harder does not happen in the braking and turn-in phase of the corner. He never brakes late and overslows the car. Pushing harder for him is the exit phase of the corner -- getting back on the gas right at the apex. He maximizes the acceleration zones, and stays on the gas as much as possible, so the car's natural tendency at the limit in such circumstances is for the rear to want to rotate anyway.

[TorontoNat]

Originally Posted by Icecreamtruk

So legit question here. Why does everyone and their mother in autoX wants their car to understeer to hell and back? Wouldnt a car that rotates easier be a lot more enjoyable to drive (and possibly quicker)? Those videos posted there. That car has very much chronic understeer (not once did it do anything other than push, push, push), yet he suggest more front bar and/or stiffer springs? Im not questionning anyone's ability here, I have never autocrossed and im just curious.

Mostly.. it's easier to be faster with but I can think of a couple more reasons why. Firstly not every one is like us, to most ppl sliding is not drifting.. it is loosing control and potentially crashing.

Secondly, AutoX is super tight and really hard to slide around. At least in my area they are really really tight, takes some really fast inputs if your gonna drift those tiny turns.

I do over all agree with you tho... Straight steering wheel turns are where it's at.... or should be where it's at at least because obviously.. this is ridiculously hard to do in practice.