Autocross Help *newbie*

[Zephyr]

I tried out autocross last month with the 5 series... I kept losing traction with my tires, using street tires with the rest of the group that was running street mods. I was wondering what is the correct type of pressure one should use? I'm totally new to this and wanna learn...so any help would be sweet or any other info you feel that i should need to know. I'm planning to maybe go to more solo2 events with this car again or wait till i get another car...

[Redlyne_mr2]

What size are your tires dude?

[Zephyr]

Originally posted by Redlyne_mr2
What size are your tires dude?

225 60 15 daytona HR

[fast95pony]

I normally add more air when autocrossing. Some people mark the sidewall of the tires with white shoe polish or chalk .This way you can see if the tires are scrubbing on the tarmac . I normally set my tires at 40 psi all the way around .
The 5 series is quite a heavy car and those tires are relatively tall and narrow.If you can , go with more performance oriented tires.
It also takes practice,lots of practice .Walk the course with other drivers and ask them what line to take. Go for a drive with the more expirenced drivers, or have them ride along with you.Try a different
line through the corners. Try to be smooth .This is my second year,and I know I have a lot to learn.
Good luck ! :thumbsup:

[rage2]

Tire pressure is the biggest deal. Marking tires is a good thing if you already have a good suspension setup. Otherwise, camber changes under cornering will roll the tire over to the sidewall regardless of tire pressure.

[Zephyr]

is there any way to reduce understeer?

[hjr]

im assuming this, but if the only thing you can adjust is the tire pressure, then what you need to do is make the front sticker relative to the back.

generally a lower pressured tire will be stickier due to a larger contact patch with the road, and the opposite would be true with high pressures.

Now this is really only useful for tires with re-enforced sidewalls, so that under cornering the sidewall will still stand up and not flop over. In your case, there isnt much you can do as you should want to run a lot of pressure in the tires to keep the sidewalls from buckling over.

You car is designed by bmw to understeer, so short of changing the suspension there is not much you can do.

You can of course try running with different pressures once you get consistent with your runs, this way you can see what works and what doesnt.

[hjr]

check out the chart on this page: http://reiff.freeservers.com/setup_chart.htm

its gives you a good starting point to understanding suspension tuning.

Just remember that you dont want your sidewalls buckling so you will need to run pretty high pressures.

[rage2]

Originally posted by Zephyr
is there any way to reduce understeer?
Don't turn in too fast ;).

[Moonracer]

Yeah if you are grossly understeering when turning in then you are coming into the turns to fast. Have your car slowed down enough so you are at the edge of adhesion but not pushing. Then punch it at the apex. Very basic info but important to do.

[CKY]

Originally posted by Moonracer
Yeah if you are grossly understeering when turning in then you are coming into the turns to fast. Have your car slowed down enough so you are at the edge of adhesion but not pushing. Then punch it at the apex. Very basic info but important to do.

easy to say, but most of us are always striving for the adrenaline and forget the basics :rolleyes:

[rage2]

Originally posted by CKY
easy to say, but most of us are always striving for the adrenaline and forget the basics :rolleyes:
Then you'll be slow :).

[Zephyr]

yea my best lap time was like 70 seconds..but then i had +2 cuz i ate 2 cones.... the fastest there was like 57... from a M3

[GTS Jeff]

Originally posted by Moonracer
Yeah if you are grossly understeering when turning in then you are coming into the turns to fast. Have your car slowed down enough so you are at the edge of adhesion but not pushing. Then punch it at the apex. Very basic info but important to do. ok well im no expert racer at all, but i wouldnt "punch" it at the apex on a balanced fr car cuz thats just asking for a spinout. but yea, understeering into corners = too fast

[speedracer]

Originally posted by Zephyr
I tried out autocross last month with the 5 series... I kept losing traction with my tires, using street tires with the rest of the group that was running street mods. I was wondering what is the correct type of pressure one should use? I'm totally new to this and wanna learn...so any help would be sweet or any other info you feel that i should need to know. I'm planning to maybe go to more solo2 events with this car again or wait till i get another car...

Again, take it for what it's worth.

IMHO:
Any car is Solo 2 material so don't worry with anyone else.

Street tires are fine. Don't worry about the guys that have fancy tires. Honestly, you won't need it until much, much later. It will take some time before you will drive beyond street tires - solo 2 is mostly skill, then preperation, and then the car.

Don't worry about "the apex" or any other racing terminology. What you should make sure is - am i driving smooth and am I hitting the cones (don't be scared of avoiding them - the closer you are the better )

(1)
Tires - Fill the tires to whatever max cold settings - eg (44psi cold)
(Bring a tire guage and compressed air)

(2)
Buy shoe polish / window marker and mark your side wall.
Where to mark? --> Look for the end of where your side tread ends. Put a line horitontal line there. You will want to do this on all four tires. Make note where the mark starts as that will be your reference.

After a run look at the tires and see if you are coming close to the marker.

If you are great ! Your using as much of the tread width as you can.

If not then you will have to adjust pressure - Add more if you are scrubbing the marker off , take off less if you are not coming close to the marker.

Leave all 4 tires the same PSI. Until youget a feel how the car handles it's not worth guessing what works and what doesn't.

Take notes on what PSI setting and how hot the day was as that will be your reference - every track day will be different.

"1" PSI makes a world of difference

[Moonracer]

Originally posted by GTS Jeff
ok well im no expert racer at all, but i wouldnt "punch" it at the apex on a balanced fr car cuz thats just asking for a spinout. but yea, understeering into corners = too fast

Well like I said very basic info, all depends on your car/conditions etc..... In my car I can pretty much floor it at the apex, I only have 140hp.

[rage2]

Originally posted by Moonracer
Well like I said very basic info, all depends on your car/conditions etc..... In my car I can pretty much floor it at the apex, I only have 140hp.
Well in that case, you're not going fast enough at the apex point ;).

[Moonracer]

Originally posted by rage2

Well in that case, you're not going fast enough at the apex point ;).

haha I beg to differ...

[rage2]

Originally posted by Moonracer
haha I beg to differ...
Take me for a ride next time you're at the AutoX... hehe.

[Moonracer]

Originally posted by rage2

Take me for a ride next time you're at the AutoX... hehe.

Ok! :thumbsup: As long as you return the favour.

[Moonracer]

Wouldn't mind doing that on the roadcourse mind you. I'm dying to get on there!!!!

[Zephyr]

ok another newbie question...

whats the "ideal" psi pressure for all different types of conditions? anyone have a list or a site that shows that?

also does the tire size make a big difference? like if i used a 17"s compared to 16"s or to 15"s

[GTS Jeff]

Originally posted by Moonracer


haha I beg to differ... i think the basic idea is that if your tires have enough traction to handle WOT, then there is a bunch of unused traction which could be used for cornering faster. u should be cornering so damn fast that u have to ease into the throttle while ure easing the wheel back towards straightness.

of course all this is easier said than done.

[240Pinoylvr]

Anohter thing you might want to study is the weight distribution to your car. some guys with hideous front weight will mount bricks in the back of their car to help with balance (of course they have the horsepower to compensate). Balance is important in Autocross. beign that its a Bimmer it should have very good distribution (the M3 is so good its scary) check it out, and see if you find more people with a 5 autocrossing. BTW, what year is your 5???

[Zephyr]

Originally posted by 240Pinoylvr
Anohter thing you might want to study is the weight distribution to your car. some guys with hideous front weight will mount bricks in the back of their car to help with balance (of course they have the horsepower to compensate). Balance is important in Autocross. beign that its a Bimmer it should have very good distribution (the M3 is so good its scary) check it out, and see if you find more people with a 5 autocrossing. BTW, what year is your 5???

1997 528i

when i was there i saw mostly M3 and a 330ci

[fast95pony]

Originally posted by Zephyr
ok another newbie question...

whats the "ideal" psi pressure for all different types of conditions? anyone have a list or a site that shows that?

also does the tire size make a big difference? like if i used a 17"s compared to 16"s or to 15"s


There's no real "ideal" psi pressure. You don't want the tires rolling off the rims , so the psi will need to be higher than for normal driving.You have to experiment with your car in different situations.
Wheel size with make a difference.Larger rims mean a larger tire contact area , however ,larger rims mean more weight and a higher overall gearing ratio ,meaning more sluggish acceleration.

[Moonracer]

Originally posted by GTS Jeff
i think the basic idea is that if your tires have enough traction to handle WOT, then there is a bunch of unused traction which could be used for cornering faster. u should be cornering so damn fast that u have to ease into the throttle while ure easing the wheel back towards straightness.

of course all this is easier said than done.

I've heard pros say there is only two positions for their gas pedal, on or off. Naturally there are some spots where you have to feather the throttle. I'm not saying that is my style however. I like to get into a little trouble and go beyond the limit just so I know where it is exactly.

[Redlyne_mr2]

Originally posted by Moonracer


I've heard pros say there is only two positions for their gas pedal, on or off. Naturally there are some spots where you have to feather the throttle. I'm not saying that is my style however. I like to get into a little trouble and go beyond the limit just so I know where it is exactly.
That seems more like a drag racer's thing rather than proper autox technique but like everything everyone has their own style

[GTS Jeff]

Originally posted by Moonracer


I've heard pros say there is only two positions for their gas pedal, on or off. Naturally there are some spots where you have to feather the throttle. I'm not saying that is my style however. I like to get into a little trouble and go beyond the limit just so I know where it is exactly. maybe if ure drifting or something :dunno: otherwise the idea of being "smooth" applies ALL driver inputs, steering, throttle, brakes.

[Moonracer]

:rofl: Whatever! I give up.

[rage2]

Originally posted by Moonracer
I've heard pros say there is only two positions for their gas pedal, on or off. Naturally there are some spots where you have to feather the throttle. I'm not saying that is my style however. I like to get into a little trouble and go beyond the limit just so I know where it is exactly.
That's my driving style too. The theory is to find and hit the limit, you must first exceed it ;). I usually get light wheelspin out of corners and a small dose of countersteer... enough wheelspin to reduce understeer, not enough to slow down exit speed (most of the time anyways haha)

I have a very agressive driving style. I enter the corner very fast, trail brake into the corner (I can get away with that because my car is a natural understeerer), helps me with my turnin, take an unconventional line to make use of my straight line power and poor cornering grip. The theory is with my AMG, it's got good power for the straights, but not the greatest in lateral grip department, so sacrafice in the corner a bit and make use of the acceleration by giving me a bit of a longer runway. Tirewear is horrible using this method though. Seemed to work well for me, pulled a few FTD's last year at the Solo2 events.

But like most of my theories, it was proven wrong lol. I gave rides to a lot of top drivers at both Solo2 and on lapping days. Every single one says I drive too hard, and that I'll be faster if I took it easier. So I spent a full day with Miles working on smoothness, and what do you know, I'm almost as fast driving smooth. A little bit slower, but damn close. Bonus is tirewear is WAY less. With work, I could probably match lap times driving smooth.

Of course, I still drive with my agressive style because it helps me find the car's limit within 3 or 4 runs allowed in Solo2 competition. Also gets heat into the tires really fast. That and it's very exciting to drive, ride, and watch :). Point is, use whatever method you're comfortable with... as long as you're making full use of the car and tires.

[three.eighteen.]

the 528 is supposed to be the best handling of the E39s

get some bigger, wider rims too with nice rubber, will definetly help

[Moonracer]

Ok indeed you must be smooth. In order to be fast on the track, be it solo 2 or roadcourse, you have to be smooth and gentle in the cockpit. There I said it! :D

[rage2]

Originally posted by Moonracer
Ok indeed you must be smooth. In order to be fast on the track, be it solo 2 or roadcourse, you have to be smooth and gentle in the cockpit. There I said it! :D
haha didn't you read my post? You DON'T need to be smooth to be fast! Agressive driving can be fast too if you can control it properly!

You can never win in this thread can you? :rofl:

[Zephyr]

ok another question....since my car is automatic... does it really make it at a disadvantage?

[speedracer]

Originally posted by Moonracer
Ok indeed you must be smooth. In order to be fast on the track, be it solo 2 or roadcourse, you have to be smooth and gentle in the cockpit. There I said it! :D

Not too smooth ;) It just has to look smooth when your really driving on ice....


Originally posted by rage2

haha didn't you read my post? You DON'T need to be smooth to be fast! Agressive driving can be fast too if you can control it properly!

You can never win in this thread can you? :rofl:
:D :rofl:

heh Rage2 is a bad example for tire wear :D


Originally posted by Zephyr
ok another question....since my car is automatic... does it really make it at a disadvantage?

Depends on how you look at it.

Auto you can be more consistant since you won't have to worry about changing gears and the gear down is more predictable.

[Tak]

Having beat Rage in his own car at a Solo2 a couple of years ago, here's my two cents....

Get some white shoe polish and make a line on your tire, going from the tread to the rim, completely across the sidewall. One line per tire should suffice for now, though some people say 3 lines per tire is stylin' ;)

Do your run.

If the white line you made has dissapeared on any portion of the sidewall, (and it isn't raining :P), then there is not enough pressure in the tire. Or your intentionally asking the tire for more than it will give (scrub). This is a low-toned screeching/howl coming from the tire, like you were spinning out.

I highly suggest just smoothing things out on the wheel, play with the throttle all you want, it's what makes driving fun :). But if you rip the front tires from traction, it will just make you frustrated.

Of course there's the ofted-said-often-forgotten "Slow down to go faster" method.

The ideal sound is a high pitch chirping or squealing. This means your tires haven't quite lost the grip on the road, the tread is squirming/stretching and this is the sound it emits when it snaps back into place. So this is what the tires are telling you. You can use this in lieu of a seat of the pants feeling until you develop it.

Rage, you up for round 2 sometime this year? :D

[Moonracer]

Originally posted by rage2

haha didn't you read my post? You DON'T need to be smooth to be fast! Agressive driving can be fast too if you can control it properly!

You can never win in this thread can you? :rofl:

There's only one way to settle this debate and you know what it is.....:tongue:

[rage2]

Originally posted by Zephyr
ok another question....since my car is automatic... does it really make it at a disadvantage?
My car was an automatic, and I was consistently one of the fastest at every event.

Originally posted by Tak
Having beat Rage in his own car at a Solo2 a couple of years ago, here's my two cents....
lol, you're lucky I just nudged a senseless cone, otherwise I would've had you by close to a second ;).

Originally posted by Tak
Rage, you up for round 2 sometime this year? :D
You bet. Wonder when the next Calgary event is...

[Moonracer]

Oooooh yeah it's on now...:rofl:

[syeve]

Originally posted by speedracer


Street tires are fine. Don't worry about the guys that have fancy tires. Honestly, you won't need it until much, much later. It will take some time before you will drive beyond street tires - solo 2 is mostly skill, then preperation, and then the car.




I agree, I went around the track with a prof. driver in a TSX with stock tires at the acura race day last year. FF and every single corner we went around I though to myself, "there is NO WAY we are going to make this!" I was truely amazed with the speed and traction shitty stock tires have if you keep the car balanced through the corners are stay VERY smooth thoughout the course. He would have ran circles around me in my RSX-S.

[240Pinoylvr]

Having an automatic tranny is not necessarily a disadvantage. Like hommie said before, it just depends. driving a automatic transmission car for me was good starting off. It eases you into the concepts of how to hit corners, how much gas to push, brake time, etc. Of ocurse I later went back to stick shift after gaining the basic concepts and i prefer stick more. But its up to your taste. and yes many automatic tranny guys are high in rankings.