mr. haison

my first time autocrossing was about a month ago in the Central Carolina Region. With VDIM on it is a major crutch. I would always push wide on all the turns and would have to slow down considerably to get the line I wanted to be on. With VDIM off, the car was a beast. I could push the car hard and it would just go. But weight really hurts this car in corners. My best run with VDIM on was 46.3 and with VDIM off it was 43.1 if that tells you anything and my second event I got second place in the novice class.

buhda

Was this at Marina? Love that place, its been awhile since I've been to an autox

chubbymike

yes, it's in Marina Airport (near monterey). Next time, I'll be going in August and i'll make sure i try it w/ VDIM off .
I definitely experienced what you described. I found myself understeering, going wide in the turns and had to slow way down (maybe it was b/c I was braking too late) and had to wait until I got on the correct line before I could floor it.
but again, I have less than 1900 miles on the car, I'm still learning the handling characterirstics of the car.

y2ks2k

Doesnt look abnormal to me, this is what my Sti looked like when being pushed and I wouldnt say it rolls much.

http://www.silverti.com/oldcars/AutoX2.JPG

ra1n

whoa mr. haison... i'm in the cary area of NC. I'm wondering where this autocross place is... fill me in!

GOBUCS

Dammmn, that is the biggest picture I have seen on any forum!!!!!! I was very close to getting an STI, but my wife could not stop laughing at the styling. I, myself had grown to accept it, but not like it. Good thing the Lexus dealer was right next to Subaru. Anyway, how does the IS sport ride/handle compared to your STI?

Lets Drive

iTrader: (3)

Yep, thats why I stated that its not an issue once you can maximize grip on proper tires. The RX-7 and C5 Z06s here are both capable of pulling over 1g in the skidpad, and great numbers in the stalom, also qualfying for super stock class.

Body roll!




You have a bigger photo though, lol

mr. haison

My first event was at the Knights Stadium in Charlotte and the second one was in Maggie Valley which is about 250 miles away from Fort Bragg. I am going to a CCR event this weekend at Lowe's Motor Speedway and running the kart course in the infield. There are like six regions in NC so there are plenty of places to go autocrossing. I just can't find the time and afford to do it every weekend or I would. There was one last weekend at the old Sanford Airport for the Tarheel region but I did not participate because it was full.

tjZ06

Glad to see somebody AutoXin' their 2IS in the area. I'll be at Marina tomorrow for the SFR SCCA event but I'll be driving my Z06 and a MK1 MR2. One of these days though I WILL AX my IS.

Oh, and the body roll is pretty bad, but not unexpected for a heavy luxury car. For those of you who have never been to Marina, it's a very high grip (as long as you don't run the first group while all the sand/grit is still on the line) surface. Higher grip than most roads you are going to find. And obviously you're throwing the car around a little harder than you would/should on the street.

Here's my car at the Duel at DeAnza which is a MUCH slower, smaller and lower grip event. And I have a 38mm front sway bar!

Inside of Turn View:


Outside of Turn View:


And that isn't even in transition, when you'd see even more roll. The car works very well and generally is only beat-out by 'race cars.' That being said, I still intend to go more than double the spring rate front, about 50% more rate in the back, and some Penskes to REALLY make this car work. But it isn't a luxo daily driver like the IS.

-TJ

lobuxracer

iTrader: (2)

Roll isn't the terror most people make it out to be. As long as the car is predictable, roll isn't a big issue - unless your suspension geometry doesn't add camber on compression and take it away on extension. It's better to have good wheel compliance than it is to have minimal body roll in almost all cases.

tjZ06

I agree, for the most part. A lot of it has to do with how you race the car, and the surface. On a road course, especially a rough/choppy one a little roll in trade of extra wheel compliance is a good thing (as you noted). For an AutoX on an extremely smooth venue like I do w/ my Z06 I'll give up some wheel compliance for less roll, and therefore faster transitions. Roll in steady-state cornering isn't that bad of a thing, as long as your have good susp. geometery (as you also noted) and a good static alignment. In a perferct world you'd have no roll in the corners (to try to plant all 4 tires as evenly as possible, as well as keep as much weight as you can on the inisde tires to use them more effectively) yet still have super complaint suspension over bumps. For most of us that isn't possible, though active dampeners, active roll bars etc. in some new cars and on the horizon will approach that ideal. My Z06 works exceptionaly well on road courses, but it is just a little "soft" and slow to tranistion for AX.

-TJ

ES3

Thx for the thread, I was thinking about giving auto-x my first try! Do you feel like it puts a lot of stress on the car/tires/brakes?

Seize

Nice pics, looks like a good time!

mr. haison

I don't think there is too much stress on the car in an autocross. I did 6 events and had plenty of tread on my tires and about 50% left on my brake pads. I then did a track day event at Carolina Motorsport Park and that ate up my front tires and brake pads and had to replace them the next month.

tjZ06

Driving style will affect consumable wear a lot. AutoX really isn’t that tough on brakes because you have short braking zones, and never build up huge amounts of brake heat (well, at least compared to Track Days). But the typical “noob” driving style is very hard on front tires, as well as exceedingly slow.

Most newer AutoXers can’t resist staying WOT too long, they don’t brake hard enough, and then they plow/push through the entire turn with the tires screaming. This is NOT the way to do it. Later as you build skill you can work on trail-braking (especially w/ a bigger/heavier car like the IS I suspect it will help AutoX times a lot, though I haven’t AX’ed my IS yet) but for now get all of your braking done early, and in a straight line. Turn in as you’re almost all the way off the brakes, but the weight of the car is still on the front end (no, this is not ‘true’ trail-braking, it’s just taking advantage of the extra front end bite while you have some weight transitioned that way) and aim for your apex with one, smooth steering input. Just before the apex begin to roll (lightly) into the throttle and continue to roll in harder as you unwind the wheel.

Imagine a solid link between your right hand and your right foot (for left trurns) or you left hand and your right foot (for right turns). As you begin to unwind the steering wheel and straighten the car out, you can apply progressively more throttle. It’s easiest to picture with a left turn, put your hands up and pretend you’re at the controls, “turn the steering wheel to the left” and imagine your right foot is off the throttle, but hovering above it. Now imagine that direct link between your right hand and right foot. As you “turn the steering wheel back towards neutral” your right foot can go down. By the time you’re going straight, you’re WOT. Once you get more practice you’ll find an underpowered, heavy car like the IS250 actually allows quicker/more aggressive throttle application, but this is somewhere to begin. And of course, once you get tail-out this whole idea goes out the window.

Try to stay ahead of the course, look a few turns past where you are, and try to learn where you have to “give it up” (aka go slower than your car is actually capable of getting through a section) in order to be setup for the next section.

Also, bring the tire pressures up to 1-2psi from their MAX rating in the front, and another 2-3psi lower in the rear (again, I haven’t experimented with my 2IS yet, but most nose-heavy RWD cars like some tire pressure bias). That will help keep the tire from rolling over so bad and wear the extreme outside of the tire as much.

Here’s some more first-time tips (don’t worry that it’s a Bay Area, CA based board, it has nothing region specific in it): http://www.baautox.com/forum/index.p...start=0&rid=84

-TJ