Autocross

[Indy 997 C4]

Hi I'm new here and I have a few questions about autocross. My dad took his 997 C4 autocrossing the other day with no idea what the best setup for the car was. He was very disappointed because he got beat by me, his 16 year old son :P. His questions are;

1. PSM on or off?

2. What tire pressure do you recommend for the 19in rims?

3. Best way to launch?

It is a 6mt that has almost no options. Thanks

[silver arrow]

Start with 42 front and rear. Borrow a tire pyrometer from someone, or buy one if you plan on autocrossing with any regularity, and bring some chaulk. Mark the front side walls with chaulk before you run. After each run look at the chaulk to see if the side walls are rolling over and check temps inside middle and rear on the fronts. Temps should show a gradient slightly cooler from inside to out. Adjust the rear increasing pressure in 1-2 psi incriments, higher to get the car to rotate better, lower pressure if the car is oversteering (or tail happy). Once you get it feeling good, write down your pressures in a notebook along with temp, surface temp, surface type. Start the next autocross with the settings you finished with the week before and adjust the same way you did the first time and again record you settings and conditions. After awhile you will have enough data to get you very close on setup from the first run. Don't forget to check tire pressures before each run.

If you get serious about autocross, a set of R comps and good alignment will be a must.

Edited April 17, 2008 by silver arrow

[swisstype]

Start with 42 front and rear. Borrow a tire pyrometer from someone, or buy one if you plan on autocrossing with any regularity, and bring some chaulk. Mark the front side walls with chaulk before you run. After each run look at the chaulk to see if the side walls are rolling over and check temps inside middle and rear on the fronts. Temps should show a gradient slightly cooler from inside to out. Adjust the rear increasing pressure in 1-2 psi incriments, higher to get the car to rotate better, lower pressure if the car is oversteering (or tail happy). Once you get it feeling good, write down your pressures in a notebook along with temp, surface temp, surface type. Start the next autocross with the settings you finished with the week before and adjust the same way you did the first time and again record you settings and conditions. After awhile you will have enough data to get you very close on setup from the first run. Don't forget to check tire pressures before each run.

If you get serious about autocross, a set of R comps and good alignment will be a must.

I did my first autocross today! I have 2006 C2S. I found 40-42 PSI worked good today, but obviously can change. I had my best laps with the PSM on, but the sport button off, so basically normal throttle mapping with the sport suspension ssetting. The PSM on and engaged for tighter setup made lots of difference in stability. The throttle response in sport was way too jumpy and made my *** end spin around too much for comfort. I had a great time and got better every run. Only one cone!

[kabel]

Autocross is not an easy thing to get right away. Tell your dad not to be too hard on himself!

Set up is not so important when first starting out. Learning how to read the course, understanding how the car handles in those situations AND having fun are the priorities.

To answer your questions IMO:

1. PSM off

2. Usually 3-5 psi over factory pressures is a good place to start with street tires. One of the main reasons for increasing tire pressures is to prevent the tire from rolling on to the sidwall.

3. Launch briskly, with as little wheel spin, no need to dump the clutch

silver arrows' advise regarding chalking the tires and keeping a notebook is spot on.

BTW, good job woopn' the old man :lol:

[Indy 997 C4]

thanks everyone for the advice I'm thinking about not telling him now so I can beat him again :P. BTW I have a MKV GTI with suspension upgrade and stock engine, he is very disapointed in himself :D

[mapoune]

You mean for Track Racing?

1 - PASM on Sport Mode

2 - PSM ON for beginning and OFF later but depend of the track type really

3 - Tyres: Recommend OEM High (F2.3 bar, R3.0 bar) and deflate it every 30mn because the tyres pressure can go up to 3.8 bar easy. then you car start to slide! :D

[kabel]

no, he was asking about autocross, like the title of the thread :wacko:

:)