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      03-30-2009, 01:05 PM   #1
Paddy
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Tips for AutoCross

Hi All,
I'm doing my first BMWCCA autocross this weekend. Any tips/ first time experiences anyone wants to share?
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      03-30-2009, 03:08 PM   #2
sayemthree
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raise tire pressure 4 to 5 psi. turn off DSC. drive like hell. steer with the throttle, have fun.
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      03-30-2009, 06:02 PM   #3
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Quote:
Originally Posted by sayemthree View Post
raise tire pressure 4 to 5 psi. turn off DSC. drive like hell. steer with the throttle, have fun.
There's two sets of values (at least there were on my e90 330i, haven't looked at the M3 ones yet), but a normal one and a higher psi one for 100mph+ with more passengers. You recommend those 100mph+ values for the track?

Thanks
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      03-30-2009, 07:31 PM   #4
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Don't worry too much about getting r-compound tires... a lot of novices worry about it. Work on technique and driving skill first.
Since you are new, I'd make the first pass using the m-dynamic settings for the dsc. It will give you a feel for the thresholds since it does allow for slide before kicking in. Disable it for a few runs since the problem I've found with dsc is that once it engages, it doesn't disengage fast enough once traction returns and slows your times.
For tire pressures, running a bit more pressure than street is normal. A easy check is to get some sidewalk chalk and run a line across the tire. After a run, you'll see how far you roll over onto the sidewall (bad) and want more pressure. If you didn't rub off chalk at all on the side wear of the treads, you have too much pressure. Each run will also heat the air within the tires and add pressure (hint; nitrogen doesn't have as much gain).
Search around on the web for driving techniques for autocross and see if they have a novice school. The driver makes the most difference in times. Walk the course several times. Get rides whenever you can and watch. Also don't get frustrated when a lesser car beats your times.... sometimes folks show up in expensive toys and just can't believe a "lesser" car can be faster--- so they start buying go-fast parts instead of seat time believing that it is the problem.
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      03-31-2009, 02:13 AM   #5
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^^^ excellent advice.
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      03-31-2009, 05:25 PM   #6
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Yes, start with a few extra psi in the tires, but leave the DSC in M-Dynamic Mode while you're a novice. I'm relatively expert and leave it on most of the time and only turn it off for certain types of turns. If you want to be fast, focus on smoothness and NOT driving with the throttle. That can look dramatic and be fun to do a little bit, but you leave tons of time every time you slide the rear out vs. moving the car forward. There's a lot to learn, so try to find some good autocross books and more detailed tips online.

Catching a ride in an expert's car and having good drivers ride in your car as you drive are two very valuable aids, for those clubs that allow it. I took a first time novice once and he gained three-seconds after riding with me for just one lap, because he didn't really have a feel for how much the car could do. He was still seconds behind me, but he improved greatly and was far from the slowest in his class.

Most clubs have an AX school once a year. Try to do that for sure.

Dave
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      04-03-2009, 08:30 PM   #7
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1. look few cones ahead
2. dont forget to use the dead pedal
3. its critical to have the proper seat position (alongside arms and legs)
4. dont ask the car to do all things 100% at the same time (steer, brake or accelerate)
5. do the first pass slowly to learn the curves, apex and bent and remember them
6. listen to instructions and be patient
applying speed comes naturally once you have a sound fundamentals
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      04-03-2009, 10:22 PM   #8
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I like ase2dais' advice in the context for beginners. Almost every rule for beginners gets turned on its head for advanced autocrossers, but those are lessons to be learned later.

I will say that some people don't "get it" about speed and drive way too slowly, not realizing the potential of their cars, particularly cars like the M3. Even at their very first event I've seen people pick up 3-seconds or more after riding with an experienced driver.

I should say that for every driver that is way too slow for their cars, there are probably five or ten that drive way too fast for their cars. For these, following the guidelines will result in speed more quickly than persisting in driving too aggressively.

Dave
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      04-05-2009, 11:28 AM   #9
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1. As soon as you pass the start line, you are only losing time.
Minimize how much time you lose. It's not just going faster, it's
spending less time on the course.

2. The trick is to drive 10/10ths. A novice will drive 7/10ths and then
not realize that they went to 13/10ths. Learn the edge and drive it.
That may mean some cones get hit and you spin. It's what teaches you
where 10/10ths is.

3. There are fast parts and there are slow parts. Learn the difference.

4. Don't square off the corners and point and shoot drive. A lot of
corners are parts of smooth arcs you can make. It's faster to drive a
smooth arc than a short straight and two jerky turns.

5. Be aggressive in chicanes. Attack them, stay in front of the turns
and as straight as you can. Getting "behind" in a chicane is a bad
thing.

6. Doing this well means being smooth. Being smooth DOES NOT mean you
are slow. To drive the car smoothly may require controlled chaos in the
car. Fast hand and foot movements do not mean you are not smooth.

7. Know your line you intend on driving. Understand it. Look for it. If
you drive such that you are forcing yourself off that line, you made a
mistake and need to slow down. The line is everything, unless you are
wrong about where the line is...then you need to change your mind.

8. Look ahead to where you want to exit the turn. Adjust your speed into
the corner to make sure your car will be on the right spot when your
exit the corner.

9. It's better to corner under acceleration than braking. Brake earlier
and then get on the throttle as quick as you can.

10. The earlier throttle points will be faster. Give up the end of the
straight to make your corner exit faster. That speed coming out of the
corner will carry thru the whole straight following the corner.

11. Do not try to save runs. If you get screwed up, go off course or mow
down cones. This saves tires.

12. Understeer is often caused by going in to a corner too hot. To
reduce understeer, straighten out the steering and/or reduce throttle
input.

13. A lift or quick stab at the brakes can cause the front of the car to
weight and allow better turn in.

14. Alignments are important.

15. If you start going slower or are less succesful than you should be,
check the car. Sometimes things change and it's hard to notice.

:arrow: 16. Seat time is more important than any performance mod

17. Autocross deliberately. Try to drive deliberately. Not just
reacting...but control the steering and drive the line. Then do it
faster.

18. Don't worry about long lists of tips. Work on one or two things at
a time. Don't try to adjust everything, put in a new swaybar and struts,
try out Hoosiers, and decide to use left foot braking all in one
weekend. Make changes one at a time and see how they feel.

19. There are many ways to setup your car and your driving can
accomodate them. Spend more time on your driving than your car setup.
Human nature is that it's easier to point to your car, or the classing,
or maybe someone else is cheating, or they spent more. But the biggest
variable in autocrossing is still always the driver.
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      04-05-2009, 11:57 AM   #10
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Excellent bullet points V1.47fan.

I think the very strongest point is the one about finding the 10-10ths point. Many people far undershoot it while others are constantly exceeding it and losing .1-seconds in half a dozen places, when the winner is often determined by .01-seconds.

For noobies it's extremely helpful to ride with experienced drivers.

I like the idea of "controlled chaos". I find that my very best runs seems like I'm constantly correcting and adjusting, but people outside the car will say, "that looked smooth". When I hear that, I know I was fast.

The big problem is that the difference between driving at 10-10ths and exceeding that is very small. Seat time, of course helps. Going to your club's school will help because you get lots more laps than at an official event, typically. I remember times where I changed my braking point by just a few feet and totally washed out a corner that I'd been nailing. The old thought of, "if that was good, then a little more will be better" isn't always true.

Dave
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      04-05-2009, 11:41 PM   #11
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Thanks guys for all the input.. I missed a lot of the later comments and only read them after the saturday autox, and believe me the all make sense now. I'm actually glad I missed them because they probably wouldn't have clicked before I ran.
Some of you dcstep for example are following my follow up post on

http://www.m3post.com/forums/showthread.php?t=248193

Thanks!
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      05-23-2009, 06:28 PM   #12
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Also try to do all your braking in a straight line, then Turn, then roll on the gas, usually combined with Un-winding the wheel.
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      05-23-2009, 09:12 PM   #13
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Quote:
Originally Posted by V1.47fan View Post
Also try to do all your braking in a straight line, then Turn, then roll on the gas, usually combined with Un-winding the wheel.
Actually, trail braking is the fast way around, but that's an advanced course. Beginners should brake in a straight line.

Dave
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Last edited by dcstep; 05-24-2009 at 08:21 AM.
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      05-24-2009, 02:21 AM   #14
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remember....brakes only slow you down!!!
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      05-24-2009, 08:22 AM   #15
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Quote:
Originally Posted by sayemthree View Post
remember....brakes only slow you down!!!

Spoken as if the writer has never driven at AX or track.
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      05-28-2009, 12:52 AM   #16
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Quote:
Originally Posted by dcstep View Post
Spoken as if the writer has never driven at AX or track.
since you have no clue I will let it out that its a famous quote from a famous scottish race car driver.

and yes i have not been on the track that much only about 15 days a year for the past 15 years. not much comapared to Jackie Stewart.
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