Here are my impressions after moving from a small turbo charged engine which I've autocrossed for a few years to a C55.

The first run was taken fairly slow with just a little tire squeal. At the end of the run, the tires were evenly warrmed up to 108 degrees across the entire thread both front and rear (tire pyrometer). Each time I pushed on the throttle, the car responded with plenty of torque. Starting old pressures 40f/44r. ~92 sec. OEM Continental tires. With the ESP on, there was no sliding in the rear.

The second run was taken a bit faster with a bit of tire scrubbing in turns. I could have taken some turns a little tighter. But at the end of the run I knew I had pushed the tires a lot harder since they were now 120 degrees across the entire tread in the front. But, in the rear, the center of the tread was 120 while the outside was a bit cooler. So, I let out a bit of air from 51 hot to 48 hot. So the pressures were now 46f/48r at 120. Time ~89.1 sec.

Last run, I tried to turn off ESP. However, since it was my first time, I kept hitting the button expecting it to light up. Finally, I gave up thinking that it was still on. However, after the slaloms where i punched the gas, it started to get loose in the rear so I figured out about 1/3 into the run that the ESP was off I learned to be a bit more careful with more gentle application of power. Time ~88.X sec. I think I could have definitely gotten the time down to 86 if I hadn't spent time fiddling with the ESP and the car hadn't gotten stuck in 1st gear for a couple of seconds.

In each of the runs, I kept the transmission set to M and I attempted to let the car shift into 2 by itself. As mentioned above, in run 3, the transmission seemed to get stuck at 6500 redline for a few seconds and I had to manually change to 2nd gear. I'm not sure if this is normal. But, then again, I don't remember if I had the throttle floored. Also, in the second run, I also had to move it back from 3rd into 2nd when I noticed a lack of power. In the third run, since I got stuck in 1st, I never got into 3rd.

During autox, I usually don't have time to look down at the dashboard to it is kinda weird not shifting with a clutch. But, overall, I think the M mode will do fine if I manually shift from 1 to 2 instead of waiting for it to happen automatically.

In turns of balance, the C55 seems very balanced. I'll report back after a few more events but I'm already starting to feel more comfortable. Even with ESP turned off, the rear is very controllable. Once it starts sliding, lifting the throttle immediately brings the rear back in line.

 

Hmm, if you're in M-mode, the car shouldn't be upshifting or downshifting by itself at all until you come to a dead stop (then it'll shift down to 1st). Are you sure the car was shifting itself in M, and you weren't accidently hitting the steering wheel buttons or the stick?

BTW, nice idea to tape your leading edges and wheel arches w/ blue tape, wish I'd thought of that before auto-Xing.

 

How does your C55 compare to your WRX in the AutoX course?

 

F-Stock? I'm told I'll be in A-Stock with my C32.