Hello there and welcome to the BMW Car Club of America.

If you are a BMW CCA member, please log in and introduce yourself in our Member Introductions section.

autocross help

Discussion in 'Autocross' started by wanesso, Jul 22, 2008.

    • Member

    wanesso

    Post Count: 152
    Likes Received:2
    I will print all these tips and instructions for reference---there are some interesting similarities between this description of autocross and competitive riding (horse, which I have done)---the mental and physical challenges are appealing-----but I realize now that I know my horse far better than the M3 right now.......
    ....and if you'all can't stand it, will certainly come back w/ feedback after my first experience at Oktoberfest.
    Thanks very much for the guidance, it's greatly appreciated.
    • Member

    Brian A

    Post Count: 659
    Likes Received:7
    wanesso:
    It would be GREAT to read a report as to how it went.

    MGarrison:
    Thank you for patiently detailing all that information regarding tires. It is beneficial to all of us.
    • Member

    MGarrison

    Post Count: 3,966
    Likes Received:254
    np Brian ;)

    Looks like we all skipped over that - I'm not familiar exactly with what's changed in whatever different M-mode options you can select, but I'd think you'd want whatever modes yield the highest performance and handling. If you have different DSC modes, you'd probably want the least obtrusive setting, and if not that, then I'd say turn it off. My recollection of reading various test reviews over the years is that the 'standard' full DSC intervenes enough that you might find it harder to get the car to do what you want. Those reviews and tests are generally higher-speed racetrack driving situations, I don't think it would be different for auto-x, as far as DSC goes. Might be something you want to play with a bit unless we get a more definitive input from someone else who's played with DSC.

    Another tip - unless your car has a fuel pickup issue when the fuel's below a certain level and in a particular handling attitude, you may not necessarily want to do your auto-x runs on a full tank of gas. E30's, for instance, when they get to about a 1/3 full gas tank, in hard left hand sweeping turns, can have the fuel move over to the far right of the gas tank, past the fuel pickup, and you can get a fuel-starvation cutout, or 'hiccup', right in the middle of the turn, when you're all committed and foot-to-the-floor. Usually not enough to cause a loss of control, but a bit unsettling if unexpected.

    Anyway - fuel is heavy, lugging less of it can help the car's handling & performance, but obviously you don't want to be under-fueled and suffer a cut-out mid-course. Sometimes an auto-x course might be fairly large, and you'd need more gas; Obviously you're safe if full-up, but it's likely more than you'll need. 3/4 full probably would be fine, 1/2 full or less might be too little (it's kind of car-specific, so I can't say exactly since I don't have specific experience in your car). If there's a lengthy drive to the auto-x course wherever it will be @ O'fest, fill up before you head there and run on whatever you got when you get there.

    Most auto-x's typically give you 3 runs, with a fair amount of time to walk the course. Since BMWCCA autocrosses typically aren't regional or national points events potentially affecting your local or national standing (like SCCA Solo 1 & 2), you may get more leeway depending on who's running the event to get a practice run or two. Unlike a driver's school where you work on mastering a track course through multiple laps, the challenge w/ auto-x is to mentally master the course, and you have a few runs to try and work it out. Obviously multiple practice runs would take some of the edge off the mental-challenge part of the event.

    I don't know, but I bet someone's probably thrown up some autocross footage on youtube.

    You got your helmet question resolved, just fyi is my response to a question earlier in the year about helmet selection for driver's schools, a couple comments there for stuff to think about down the road sometime, possibly -

    http://www.bmwcca.org/forum/showthread.php?t=748
    • Member

    wanesso

    Post Count: 152
    Likes Received:2
    Excellent and helpful information--I read the helmet suggestions too. I was just about to ask the gas tank question and you read my mind. I certainly notice a difference in regular diriving when the tank is full---I'll aim for 1/2 tank if it's feasible------will try both on and off positions of the DSC (assuming I remember this while nervous) and engage the M-dynamic settings--there is also an additional "power" button which I suppose should be engaged or tried once perhaps. The aim is not spin out but quick start so it may be over doing. Thank you and everyone else who has been so informative, reassuring, and helpful!
    • Member

    CRKrieger

    Post Count: 1,616
    Likes Received:21
    Unless we sidetrack you in the bar. I'll be there. I'm guessing Marshall will be there, too. Many beers will die.

    As for steering, Marshall didn't tell you quite enough. There is still time for you to learn to shuffle steer. This keeps each hand on its respective side of the steering wheel so you aren't reaching across your chest to steer.

    The best wheel control you have is with your hands at 9 and 3 o'clock. This applies whether you are going in a straight line or in a tight turn. We can (and do) teach this on a skidpad circle. Unfortunately, it's harder to find a place where you can privately drive as fast as your car will go in 200' circles. Nonetheless, you can practice shuffle steering at any normal intersection.

    As you approach, reach to the top of the wheel with the hand toward the direction you will turn. When you go to turn, pull down with the top grip as you release and lightly run your opposite hand to the bottom. When your hands meet, switch the grip from one hand to the other and smoothly continue turning the wheel as you lightly run the other hand to the top. You can repeat this until your turn-in is done (won't be as much with a 'tight' steering box like the M3's). To return to straight ahead, reverse the process. You can see this takes your hands top to bottom of the wheel at the same time with one or the other, but not both, gripping it.

    That's the principle. The first variation is to start with your grip at the bottom, but everything else is the same. You just start with a different hand. The next variation is to learn how much steering input your car needs for different turns. This is subjective for each car, so you need to know yours. It would not be the same if you drive my car.

    For relatively long (over 90º) or 'sweeper' turns, you want to get your hands into that 9/3 position, or close to it, for most of the turn. What you can do is learn to anticipate how much steering input you will need so you can get your hands there. As you approach such a turn, shift them away from 9/3 so that when you turn, they will be there. Then, if you have any slight corrections to make, or a slide to correct, you can do it without having your arms all crossed up.

    Know that there is philosophical disagreement among instructors whether this is the 'best' way or not. More autocrossers favor shuffle steering than do track drivers simply because there are very few track turns where a hand shift is needed, but quite a few on autocross courses. Some instructors are adamant about it. I am not. Try different approaches based on what you know about them. DO NOT try the approach that Marshall also discourages for at least two reasons he didn't mention: 1) your control from a grip inside the wheel is lousy and 2) if something happens to trigger the airbag while your hand is in there, you will likely get a broken wrist and/or fingers as well as getting a chance to break your own nose with said broken body parts.
    • Member

    wanesso

    Post Count: 152
    Likes Received:2
    steering practice

    OK--how much of this can I practice on the street or an empty parking lot without getting into trouble?

    ...and right now my tires are 22psi in front and 24in back----should I be nervous about going up to 40psi?
    • Member

    wanesso

    Post Count: 152
    Likes Received:2
    steering thru the intersections

    .
    ..going out now to practice that shuffle----you are an instructor?
    • Member

    CRKrieger

    Post Count: 1,616
    Likes Received:21
    Yeah ... although some people may find that frightening. I did SCCA autocross instruction some 15 years ago. Regularly at Road America with Badger Bimmers otherwise.

    40 psi should be no problem. I have actually run as high as 50 with one particular understeering pig I owned. It may be best to start with your recommended stock pressures. Are they really that low?

    As for what you can get away with in parking lots, I have no idea. It certainly helps if you own it ...
    • Member

    mattm

    Post Count: 253
    Likes Received:11

Share This Page