Boulder, you may not have been dealing with power oversteer. With "excessive speed by the driver" on a good line while lightly rolling on the throttle, you may not have been feeding enough power to the rear to keep it planted, especially in a fast downhill sweeper where the rear will already be a bit unloaded.

Let's talk PSM. I tracked on it for years, and all things considered, it's a good system. It rewards smoothness... meaning it doesn't step in even when "on". You can get some decent slide in the tires without the sytem intervening, but smoothness is the key. Get jerky, and it reels you in. With it turned "off", you can get into trouble even though it's still 'there' in the background. It allows a decent amount play, sort of, but you never really know if you're saving the car or the electronics are... it confuses the learning process.

PSM IMO can be a constructive tool, but I feel that it builds false confidence. It makes you think you're a better driver than you are since the electronics intervene so quickly... sometimes without the driver even knowing it. You may feel nothing yet see the little yellow PSM idiot light flashing furiously for a second or two. It'll save you even before you know what's going on. It prevents you from driving on the edge and thus limits your learning experience.

In the GT3, I don't miss PSM at all. I've learned to trust this car, and it's limits are exceptional. The GT3 is predictable, and it's pure joy exploring this car's handling nuances.

I'm with Bob. PSM would have intervened in your downhill deal, and my guess is that it may have cut throttle and applied brake to the rear independent of the front.

Cheers

 

I have to completely agree with what RJFabCab sad: Boulder, you may not have been dealing with power oversteer. With "excessive speed by the driver" on a good line while lightly rolling on the throttle, you may not have been feeding enough power to the rear to keep it planted, especially in a fast downhill sweeper where the rear will already be a bit unloaded.

Rolling on it pretty gently will NOT set the back of the car. Unless you are on the power, and unwinding the wheel to widen your arc, you are driving your car in a very unstable condition. Rear-engine cars, no matter how advanced they are, do not like neutral throttle. They need pressure on the rear tires to counteract the weight and pendulum effect of the motor. That "pressure" comes from the weight shift created by you being on the gas.

Neutral throttle is for the BMW crowd. Foot to the floor is for Porsches!

 

I also agree.

That's the way I get my car to turn in for some corners.

By coming in little too fast, trail braking and then either being light on the throttle or lifting slighly. Once the rear is coming out, then you can add more throttle and control the rotation with throttle but before the real "steps out", often it does it by being light on the throttle, or lifting.

i hope that makes any sense,little difficult to explain.

 

Since most have chimed in about how to correct, etc, then my question would be:

And why would you be on a track like this to begin with? A 3rd gear sweeper downhill with a 9" drop down a rocky hill???

Was this a "open road" track or a closed circuit road course?

 

Probably the right question to ask with the modfier of "why would you be so close to the limits on a track like this"?


It was a closed circuit road course. The why is because our track situation in Colorado is very bleak. It's this or nothing right now. That is why I was by you in LV a few weeks ago and why I'll be at the new Miller track in SLC. I don't screw around on the street. The faster my cars have become the more cautious I am on the street. In fact, with the dozen or so 911's I've had I think my favorite on the street was an '86 carrera. You could let it run some and have a good time just driving. The newer ones take too much speed on the street to be safe.

It was probably my 20th pass through the turn that day. The rear tires were probably 4lbs high and I am going to adjust the rear sway. It was loose in the back but there was nothing else to give in the front. Just bad judgement at a bad place on my part.

 

Totally forgot about you telling me recently about your track opportunties of in CO. You are spot on in the re-wording of my question. I just forgot about the lack of quality tracks near you. Good point.

One of the requirements my wife and I had when deciding on where to move to form Vegas we had "proximity to great tracks" on our list of requirements We settled on NC and its central location to ALOT of great tracks.

Now that Miller track is something to look forward to

 

Don't do it, take it from a guy who tracks his Turbo with PSM off.

Unlike the BMW DSC, the PSM is neve really off. Which begs the question, who is driving the car? You or the computer?

In fact, it bothers me so much that I am actually selling the Turbo to get either a GT2 or a GT3.

Oh and PSM will not save you on any momentum induced oversteer. It is only good at saving people from over enthusiastic throttle application in the turn. The kind of ham fisted driving that will get you in trouble with your instructor on your first ever DE. Try this at your own risk. When I first got the Turbo, I was in a situation where I got into a momentum induced tank slapper because I was not expecting it. PSM was off, and it did exactly nothing. I had to use what I learned in DE to save the car.

Afterwards, I did a test with PSM off. I would at street speed in 1st, stomp on the throttle mid corner, and sure enough, PSM cuts power, redistribute power, and bring the car inline without me even doing any correction (mild exxageration).

Oh, and if you ever triggered the ABS on the track (say trail braking and you were not smooth enough on the brakes), PSM will turn itself fully on and do all sorts of fun things.

In short, PSM sucks, GT2/3 pwnz all, and I am getting me one of those and getting rid of the self driving Turbo.

 

It's my understanding of PSM that it will "save" you in both those situations. It either cuts power or applies brake to individual wheels...

 

Did not do it for me in either.

The tank slapper was at around 70mph, I did a quick left right transition to avoid some big debris on the freeway. And off the rear end goes.

I did that same manuver in the E46 M3 with DSC off a few years back, and it was no big thing.

I will be happy to demonstrate if we were meet up at Button Willow or some track around here (no, not on the track).

 

You had PSM off thought, right? Again, correct me if I'm wrong, but when PSM is off it only re- intervenes when you really screw up and hit the brakes (or invoke ABS on 997)...

If you're the same SY Turbo I've seen at Open Track events, that's the fastest Turbo in the west!

 

Yes, I had the PSM off and got myself in a tank slapper situation.

I guess I am trying to make two points.

1. PSM, when off, still will not let you stomp on the throttle mid corner.

2. Following 1, it should have been able to save my from my tank slapper even though I had it off.

As far as fastest Turbo in the west, that's not me. I only do BMW events because I am po and can't afford to write off the Turbo with my own pocket.

I am trying to caution people that PSM really makes you second guess yourself. And I just as soon not have it. If I screw up, fine, I screw up. None of this maybe, perhaps, possibly, was it me or was it the computer deal.

 

exactly!

Great points earlier, the theme is sometimes you need to set up for your style of driving, not statistically correct settings on the car (reference Fernando Alonso and his craving for understeer).

btw, God would approve of Russell School and infinity amounts of open wheel and shifter kart time.

 

I never turn off psm on my turbo when on the track. It rarely comes on or interferes if you drive it as smooth as you can.

 

But why have it then? The second guessing part is why I am getting rid of it.

PSM, PASM, TC, how about just plain ole DE? Oh, and many (not saying you) Turbo "fast" drivers on track wear down their rear pads faster than the fronts.

Hmmm, why do you think that is?

 

I won't have it as I'm expecting my 997 GT3 Club Sport this month. Turbo S will be sold.

The TC in the 997 GT3 can be turned off if that's what you want. In my case, I'd leave it on for the first few track days so I can get used to the car.