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View Full Version : First Autocross in the A4 on Sunday



Yaktizzle417
03-04-2008, 05:46 PM
I'm all stock sport suspension, but with OEM+ replaced lower suspension parts very recently. I'm on a super light BBS 16in wheel with Fuzion ZR-H all seasons, 205/xx/16 all the way around. Brakes have 80% life left, and were recently flushed.

What tire pressure should I run? Its going to be about 55*, and my car has no spare, no extra weight whatsoever like subs and the widowmaker and stuff. I'm still going to run with a full interior, I don't want to get bumped up any more than I have to be.

Anything to look for?
How much is this going to rape my cars suspension?
The track is usually fairly aggressive, and generally has a few downhill sharp corners, which I'm worried I'll plow right through. Is there anyway to at least combat the understeer? I've read the Audi track book, and my dads been to a few BMW Driving Schools, and I've autocrossed his E36 before... but never my car.

My dad and I are having a contest to see who can put down the fastest times in my car. His ///M just got a new clutch and stuff so we can't beat on it for a while. [=(]

I'll post up a ton of pics and hopefully a few videos.

Thanks for the input guys.

Kyle H
03-04-2008, 06:33 PM
AHH I had a great response all typed out then I accidentally closed my window.... shit!

basically, run the rears at just about their max pressure and the front tires at 1/2psi less, stay on the gas to pull out of the corners even if your car is pushing, walk the course a lot before you drive, go slow in the beginning until you get a feel for the course (slow is smooth, smooth is fast [;)] [i stole this quote from somebody a couple days ago, i love it]).

Just remember to slow down before the turns and accelerate out, be thinking of the next turn and where you need to be, etc etc...

If you have any 20oz c02 tanks from paintball, take a couple of those and spray down your intercooler before your runs (and not your dads). [:D]

Yaktizzle417
03-04-2008, 07:47 PM
Really KYLE!??!

I should WALK THE COURSE!?!?!?


Lol, you know I've been in Solo2 for a while...

Max would be like 40 right? I've been at 32 all the way around this winter and some warm days.

So just get an on/off, turn the tank upside down, and spray it? When the car is still running or after its turned off?

djwimbo
03-04-2008, 07:55 PM
most tires are maxed @ 44 psi. Considering you're using All seasons I'd go w/ 40psi.

Other than that, sounds like you have a pretty good idea what you're doing.

onemoremile
03-04-2008, 08:24 PM
I'd also go with 38-42 psi. Understeer is the nature of the beast. Slow in, fast out. Late apex turns are the way to go.

Yaktizzle417
03-04-2008, 10:33 PM
Yeah, I've always been able to put the slow in - fast out method down onto pavement, but I'm not quite sure I really have a solid understanding of apexing corners. As I take a corner, I approach outside, brake/downshift if necessary, reach the middle (turn in point?) at around 1/4 to 1/2 throttle, then exit outside. From the ACNA book, it seems that this is the Geometric Apex. I'll experiment on the first runs, maybe that'll help.

I've never had a good driver or instructor ride with me during Solo2 events, which I think is the real reason why I can't really "see" early/late apexes.

Kyle H
03-04-2008, 11:54 PM
Really KYLE!??!
I should WALK THE COURSE!?!?!?
Lol, you know I've been in Solo2 for a while...

shut the hell up, i also know you like to run off of mountain roads. [;)] I was rushing and giving my response half-assed (because it got deleted the first time) and didn't remember you used to autox.



So just get an on/off, turn the tank upside down, and spray it? When the car is still running or after its turned off?

turn the car off (i've heard c02 in a running engine is bad), and yeah just use an on/off with some macro attached to it to aim at the smic. I've never tried it but I always thought it would be a good idea to kill heatsoak between runs.

Yaktizzle417
03-05-2008, 12:09 AM
Lol, its all good bro. && No accidents or even close to accidents in what should've been my first car yet.. so its all good right?

Hrm..

This may be a bitch with my stock SMIC in.. I haven't had time to have my FMIC done. With this shitty weather and my dads clutch being replaced, I've been carless on perfect days to install it on. =[

onemoremile
03-05-2008, 10:10 AM
The light blue is a late apex line. Brake in a straight line and add a bit of steering at the end of the braking zone (trail braking) to get the turn started. Coast until you can see past the apex and then floor it. Depending on how quickly your turbo responds you may be able to floor it earlier. Hitting the apex is absolutely critical to getting around corners quickly.

The other trick is with slaloms. Always try to clip the base of the cone with the inside rear tire. This helps you visualize where and when to change directions.

http://upload.wikimedia.org/wikipedia/commons/thumb/b/b7/Racing_line.svg/600px-Racing_line.svg.png

maxspeed
03-05-2008, 10:21 AM
oversteer understeer

djwimbo
03-05-2008, 12:55 PM
great diagram. I was about to draw one up, but he beat me to it.

One thing I had to learn quickly is to always brake in a straight line. Not only will this increase the cars ability to shed speed, but will also allow the car to be accelerating or at least maintaining momentum through the corner.
I wouldn't have believed that I was doing it, but this photo proved it to me. And this is the old car, not the current and my first AutoX.
http://photos-f.ak.facebook.com/photos-ak-sf2p/v148/126/82/633539761/n633539761_345069_1798.jpg

Solaris
03-05-2008, 01:07 PM
One thing I had to learn quickly is to always brake in a straight line. Not only will this increase the cars ability to shed speed, but will also allow the car to be accelerating or at least maintaining momentum through the corner.
I wouldn't have believed that I was doing it, but this photo proved it to me. And this is the old car, not the current and my first AutoX.


Plus, braking before turn-in gets the suspension settled. You aren't steering with more weight on the front wheels and less weight on the rear wheels.

onemoremile
03-06-2008, 09:07 PM
Right at the end of the braking zone you can flick it into the turn. This is textbook trail braking and a good way to get a car that is prone to understeer to turn in. This is because the fronts have enough weight for good traction but speed is low enough to avoid plowing over the cones. The rear is still light enough to be unsettled and kick out. It is trickier than it sounds to get right. If it doesn't work then try running wacky tire pressures like 38-42 up front and 28-30 in the rear.

Yaktizzle417
03-06-2008, 10:27 PM
Really? I would've figured you'd almost reverse that?

Well, depending on how the first run goes, we'll see what happens.

I wish I could just do the whole damn thing in third.. 2nd sucks for me =[

djwimbo
03-07-2008, 11:40 AM
I like cars that are prone to oversteer though. Maybe it's b/c I'm a novice when it comes to sanctioned racing. It just seems easier to control. ... However the B5Q is definitely prone to oversteer in the snow, at least for me [:)]
I didn't have too many issues when I ran the old car, I picked up a good amount of time in between my runs b/c I started to get comfortable with it.

How did it go by the way? did you beat up on your dad?

onemoremile
03-07-2008, 11:47 AM
Really? I would've figured you'd almost reverse that?

Well, depending on how the first run goes, we'll see what happens.

I wish I could just do the whole damn thing in third.. 2nd sucks for me =[

More pressure = more traction. Less pressure leaves less contact patch on the ground which limits grip. What works for autocross at 15-50 mph is very different from what works on a real track at 50-130mph. A very competitive autocross setup would be geared toward instability and therefore be twitchy and scary to drive on the freeway. Great autocross alignments usually have a touch of toe out front and rear and about 2-3 degrees negative camber. I ran with the South Bend group for awhile and they've got several national champions down there. Lots of Topeka patches on those jackets.

Yaktizzle417
03-07-2008, 03:09 PM
Ah, that makes sense. TWO MORE DAYS!!

I'm so excited!

AB18
03-07-2008, 03:19 PM
Auto-cross must be alot different then other setups. Because in all my racing expeirance, more tire pressure, does not equal more traction.

onemoremile
03-07-2008, 04:12 PM
It's true. We first met all the Topeka veterans at the SBR-SCCA autocross school at the Tire Rack. We ran countless laps on their track and my roommate and I set FTD and runner up over some much better cars. The setup in autocross often counts more than the car itself.


This is one of the best autocross setup guides around.
http://www.wtrscca.org/tech.htm


Steady state understeer
If front tire temps are optimum and rears are low, stiffen rear antiroll bar; if front temps are too hot, soften front (most likely).
If front tire pressures are optimum, decrease rear tire pressure. Increase if chunking occurs.
Improper front camber.
Too much body roll at front, causing excessive camber change.

Yaktizzle417
03-09-2008, 03:50 AM
omgz its 4:47 and I have to be at the track at 9!

I can't sleep!

haha

djwimbo
03-09-2008, 05:56 AM
it's 7:50am here, better get crackin' .... and I've only been up since 3pm. You better post some of the pictures up. ASAP. I wanna see 'em.

Yaktizzle417
03-09-2008, 07:45 PM
Well, I was about to take two pictures.

Me and my buddy pulling up to the registration gate

And the exit lane.

"New SCCA rules mandate that you have to have a legal guardian present at all times, even if you're just watching. Now you need to leave."

I'm furious. It seems like they want us to go hit curvies on streets and risk all kinds of death traps, rather than hitting a few cones. I kept my cool, and left when he told me too, but I was so pissed. Then the guy that kicked us out hit vtec in his Si right by us while we were sitting in an empty parking lot up the road. I don't get it.

All that work to get the cars ready to go and all the excitement building up to finally autocross my car, and it gets ruined by new rules and my dad having to stay an extra night out of town.

He got back in at 12, and registration closed at 10:30.

Gahhh.

Oh well, now I can order a sway bar and finally get some turbo goodies and stuff installed.

=[

djwimbo
03-10-2008, 04:05 PM
Weak sauce. I thought they required a SCCA license for any event in 2008+ too? or did I hear that wrongly somewhere?

Yaktizzle417
03-10-2008, 08:52 PM
Just a membership, not a license.

If you arent a member, you have to buy a weekend pass.

djwimbo
03-10-2008, 10:29 PM
my bad, right thought wrong term. I keep forgetting to get my membership when I have money.

UCFQuattroguy
03-11-2008, 07:13 AM
Here are a couple pics from my action this past sunday here in Orlando.
My current setup uses Vogtland Club Spec springs, Bilstein dampers, H-Sport swaybars. The car performs VERY well considering it's still on street tires (Falken RT-615).

http://pictureposter.audiworld.com/72544/march_1.jpg

http://pictureposter.audiworld.com/72544/march_2.jpg

Yaktizzle417
03-11-2008, 09:05 AM
Thats probably the suspension set up I'm going with!

Thanks for the good news haha!

=]

onemoremile
03-11-2008, 11:47 AM
I'd go with Konis. The Bilsteins will be slightly sharper at turn-in but rougher and more harsh everywhere. The Konis will be more supple and keep the tires planted better on the typical autocross parking lot. They are also much more comfortable for daily driving.

The S4 Avant has Vogtland springs over Konis with the H-Sport ARBs and it is more comfortable than my A4 Avant with the same bars and stock sport suspension. It is dramatically more comfortable than my old KW V1 coilovers which shook the hell out of the car and are responsible for all the creaks and rattles that still persist.

Another option is the Shine Racing real street suspension. Dick Shine really knows his stuff. Excellent porn name too!

Yaktizzle417
03-11-2008, 06:57 PM
Well with the looks of my new job, I can get some coilovers!

Sway bars come in like 2 weeks too!

djwimbo
03-11-2008, 10:30 PM
I read up on the Bilstein PSS9's and turns out they really aren't worth the money either. Same goes for the Tein's. Which depending on how much you're planning on dropping cash-wise makes a big difference too.
I've heard some really good reviews on These "Gran Turismo" (http://www.startupracing.com/Contents/Products/B5/B5ProductsSuspension.htm). Not cheap but the couple people I've talked to about them say they are worth every penny.

Yaktizzle417
03-11-2008, 10:33 PM
Thats about what I was looking on spending..

Tein's have never impressed me, but the PSS-9's is kindof a surprise to me.

djwimbo
03-11-2008, 10:59 PM
I started doing some research on the PSS9 system as I try to live the motto "You get what you pay for". Turns out, after doing some research, they're not all they're cracked up to be. If I was to do it in a more budget minded application I'd be rollin in their strut/spring setup. It's not too bad pricewise, and ride is ok. As I consider myself a novice AutoCrosser I'm learning more of what I like and how I want my car to react.
This season is pretty much gettin used to a Quattro car, and possibly a little tweaking in the alignment.