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Benno
07-23-2015, 09:31 AM
Got to autocross my 330i ZHP recently. In order to maintain marital harmony it is an automatic but it was still a great experience and I'm looking forward to more opportunities. It was a little wet, I have not done an autocross in several years and never with rear wheel drive and I was over-eager on the throttle through most of the turns. Times were not great but the fun was off the chart!

Anyway, I alternated between sport and manual transmission modes between runs and I can't tell which was better. In manual I would put it in first and when I would go to up-shift it was already in second without bouncing off the rev limiter. As far as I could tell in the brief flurry of activity on each of those runs it stayed in second the remainder of the run. That was fine but there was a Chicago box that I wanted to down-shift while exiting (more for fun than for time and technique). In sport mode I wasn't sure if it was starting off in first and there was no obvious shift into first and I'm sure that on one run on a long curve it went into third. I've read some threads on how the Steptronic handles these situations and I don't see a definite answer out there (http://www.zhpmafia.com/forums/showthread.php?14739-Steptronic-1st-gear-usage&highlight=Steptronic). It may need to learn to shift more aggressively and stay lower but I'm not so sure I want to risk getting tickets on my way to an event.

Maybe I'll stick to the manual mode and down-shift when I feel the need and let the fail-safe up-shift at the redline. Surely anyone serious about autocross will be driving the 6MT but if any of you have some thought on it I'm listening.

I also tried the stability control off and on and came to the conclusion that off is better with the possible exception of fully wet courses. It was more satisfying recovering from oversteer without aid, not to mention it elevated the fun factor. My best time was with it off and driving just slightly past the point of complete control.

Tires are Extremecontact DWS and overall the all stock suspension felt fairly solid though I couldn't help myself pushing past the limit of grip. Maybe it was because the course was damp but I was a little surprised at the oversteer. I had read that the stock suspension tended to understeer. I have no complaint about that effect - understeer causes feelings of disappointment while oversteer causes feelings of excitement bordering on fear.

Overall I'm not too concerned if I don't improve my times a lot but any tips will help me out. Also, could anyone confirm F Street class and a pax modifier of 0.810 for the stock ZHP?

johnrando
07-23-2015, 07:08 PM
Awesome, sounds fun. Good detail.

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Dave1027
07-24-2015, 08:39 AM
Anyway, I alternated between sport and manual transmission modes between runs and I can't tell which was better. In manual I would put it in first and when I would go to up-shift it was already in second without bouncing off the rev limiter. As far as I could tell in the brief flurry of activity on each of those runs it stayed in second the remainder of the run. That was fine but there was a Chicago box that I wanted to down-shift while exiting (more for fun than for time and technique). In sport mode I wasn't sure if it was starting off in first and there was no obvious shift into first and I'm sure that on one run on a long curve it went into third. I've read some threads on how the Steptronic handles these situations and I don't see a definite answer out there (http://www.zhpmafia.com/forums/showt...ght=Steptronic). It may need to learn to shift more aggressively and stay lower but I'm not so sure I want to risk getting tickets on my way to an event. Maybe I'll stick to the manual mode and down-shift when I feel the need and let the fail-safe up-shift at the redline.

I'd just use sport mode. That way you could focus on the course and not have to be distracted by shifting at the right time. Sport mode will hold it close to redline when you are into the gas. It will also automatically downshift when you hit the brakes. The Step engages 1st gear when it "thinks" it's correct to do so.

Benno
07-25-2015, 06:31 AM
Yes, I definitely need to concentrate on the cones and sport mode would be the choice for that. I may still try manual now and then but since it up-shifts on its own it doesn't seem to be well suited to this.

Looking forward to another event coming up. Part of the fun is learning what improves times. I'm not going to try to set this car up for autocross or track necessarily but I may get a set of summer UHP tires now that I've got extra wheels (thanks JR) and I may need to replace my control arm bushings so I'm looking into polyurethane. Of course the biggest improvement I can make is the driver!

johnrando
07-25-2015, 09:28 PM
YW. Try the paddle shift mod, c/b more fun w auto cross.

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