Cogito_Ergo_Zoom

Will be spending Sat & Sun at Cresson MSR with the Driver's Edge guys. Very excited to get the car on the track for the first time.

Any tips about MSR are greatly appreciated. Not my first DE, but my first time in a 991 and first time on this track.

Nugget

I'm about to hit the road from Houston. See you tomorrow!

Cogito_Ergo_Zoom

Cool! I think you might be my instructor...

And we probably have a mutual friend, too. Drives a red Cayman S, lives in Austin.

Cogito_Ergo_Zoom

Wow, what a great experience my first DE in the 991 was. As much fun as you can legally have. The car was a blast on the track and I know it's limit tendencies so much better now. Even got crazy and ran with PSM off in my last session (with mixed results but ending in a gigantic smile).

Thanks, Nugget for being such a great instructor. Already looking forward to my second crack at Big Ben with the PSM off again.

dasams

Why track a new car on a new (to you) track with PSM off? It doesn't hurt anything when traction is good and just might save an off Dave

Cogito_Ergo_Zoom

Good question. I'll try to answer it. It was mainly for rational reasons.

I'll preface it with the fact that I only drove with PSM off on my last session on the last day, with my instructor briefed before while we were lined up on the grid, and I only switched it off after the tires were warmed up and up to pressure. By the end of the last day I was getting pretty comfortable with both the track layout and how my car was responding nearer the limit, so I thought it was a good time to try. My instructor for that weekend (and who's also on this forum) drives a .1 GT3 RS which doesn't even have PSM, so I knew he'd be ready to give me the proper guidance I would need. He'd kept me suitably reined in up to that point in the weekend, and we even went through a "pre-flight checklist" during the warm-up lap about which corners I might need to take a different approach than I had up until that point.

Okay, so the reasons were basically thus:

1) It was one of the goals I set for the weekend. I came to the track to push my car and myself to the limits. That's what the track is for, IMHO. I've heard several theories about exactly where and how PSM intervenes and I wanted to confirm this in a (more) controlled environment. I now know this very well from my own experience, which to me personally is invaluable. When PSM is off, it's really off. It will let the rear go and send you off the road if you make a big enough mistake.

2) Several people in the paddock, some in extremely fast cars in more advanced run groups than me, were telling me about how they were "flat out" in some of the challenging sections, but then with a little prodding admitting that their stability control systems were indeed intervening in several of the corners. I wanted to know that if I nailed a corner it was me doing it and not my PSM managing it for me. There's no better teacher than experience when you've got the car in a lurid tail-out slide through a fast corner to let you know that you have indeed got it wrong.

3) I respected--and even feared--the car more with the PSM off which resulted in me (according to feedback from my instructor) driving the car much more smoothly than I had all weekend. He even said "we should have turned PSM off a long time ago" at one point. There's just something wrong (in my book) about driving a car as capable as ours on the track with impunity knowing you are doing so because you've got an electronic insurance policy saving your hide if you're overly bold or aggressive. One of the things that used to separate 911 drivers from the rest of the pack in the old days was the ever present threat of the car swapping ends and sending you off the road in dramatic fashion if you did foolish things at the controls. If you could master a 911, you could drive anything.

4) My ambitions ultimately lie beyond just doing DE days in my road car. I want to buy a race car and actually race it one day when I'm ready for that. DE days for me are part of that learning process. (Doing a professional 3 or 4 day racing school will be, too.) A Cup car or Pro Mazda won't have stability control to save you if you get it wrong, so better to start learning the lessons now.

So in the spirit of full disclosure I will admit that on the next to the last lap I lost the rear of the car through one of the fastest corners on the track, a difficult downhill, off-camber 3rd gear corner where the car is loaded up heavily and you're at full throttle well before the exit. At the end of the short straight following it you're doing approximately 110mph. I'm happy to say I didn't let it spin though, but by the time I caught it we were pointed at the infield grass on the inside of the corner and we did a little groundskeeping. My instructor helpfully reminded me it was just part of the learning process and I was just elated that I had done it with no damage to the car or to anyone/anything else. Risky yes, but to me it was an essential part of the weekend. I learned more in that last session about myself and my car than I had all weekend.

On the long drive home from the track that evening, I replayed the whole thing in my mind again. I realized that I had made a several crucial mistakes: (1) I came in too fast and at the same time (2) turned into the corner too early, which meant (3) I had wound on a load of extra lock and lifted (4) to wrestle the car back onto line, all the while staring down the apex cone (5) instead of keeping my eyes up and focused on the exit. I (6) picked up the throttle too early and got too greedy trying to "rush" back to full throttle as the exit approached. The inevitable outcome of these compounding mistakes, of course, was a car that began to oversteer.

Had I just kept my eyes on the exit point and unwound the steering progressively as I applied the throttle it probably wouldn't have happened.

Would I have learned this hard lesson had I just seen the PSM light flicker for an instant and kept moving along? Probably not.

kyrocks

You are correct...driving without PSM will make you drive smoother and respect the car.
You learn more with it off and it also saves rear brake pads. Just don't be stupid. Remember, the 991 is the easiest 911 to drive.

Cogito_Ergo_Zoom

After riding along in a 997.1 RS a couple of times that weekend, I don't disagree.