Yes, PSM can cost you several seconds per lap without a doubt.

 

All who complain about PSM on state of affairs are not smooth drivers. If you are smooth you won’t even notice PSM (only if you make a mistake – and quite frankly I would be thanking PSM afterwards if I could). People who slide around should buy BMW’s as they certainly look spectacular with a loose rear but it is in fact slow driving. Only handful of racers, are quicker with PSM off only if using technique of trail braking. It’s very easy to be a local hero at a local track (complaining about PSM slowing you down) until a pro driver takes 10 second off your lap with PSM on. It’s therefore pointless debating if the car is better with PSM on or off until you are driving within a second of a pro – same car, same track. Once you have 400bhp+ in a car or 130bhp+ on a bike it’s all in the pilot - driver/rider. I see 1000cc riders with 180bhp being killed off by 600cc riders with 130bhp. PSM has absolutely nothing to do with it. I wish people would stop overestimating their driving abilities.

Four days ago Michael Schumacher was at the Pannonia Ring (one of my local racing tracks) on a motorbike. He came first in a race. He wiped 10+ seconds of my best lap time and he was about 6-7 seconds behind the lap time record holder. So, it’s all in the pilot and the better I get the more I am learning how clueless and crap I am. And the last second where the winners are? That’s the most difficult one to take off and that’s what we are talking about where the difference with PSM on or off is.

 

That statement is a joke. And your MS story has nothing to do with PSM.

You dont take in any way account of suspension, alignment and tire differences affects on the geometry of the car. When you can carry far more G's than a stock vehicle that has yaw sensors that have preset controls to step in while possibly thinking you are out of control it can get a bit fuzzy.


One thing is for sure, Porsche engineers can design a system for a stock car, but they cant deisgn it to fit every level of modifications.

There is much more to say, but I'm not going to get into it yet.

 

KHM, well when someone calls me a joker I get just a tad upset. And you would be who? One of those “racing drivers” who knows it all. May I ask where do you race mostly? When not at Barber, I presume in bars with your palls boozing beers discussing PSM techno babble? Maybe I am mistaking but please tell me if I should have noticed you racing in a Porsche Turbo Cup? I can't belive there is no-one at Barber who could explain this to you? Tell you what, why don’t we meet at Nurburgring; you switch the PSM off and align you car anyway you want, and I will switch mine on, and let’s see. I am not going to go into it either... Anyone who starts a sentence with seeking an argument; “this story is a joke” is a “racing tosspot” as far as I am concerned – no offence. If Walter drives the car within a second with it on and with it off than you must be “bloody good” to share your wisdom on this forum. Also if you would have read the racing perspective on PSM just a page back properly you would not be talking the geometry and tyres nonsense! PSM allows 7% slippage. If you consider yourself to be any kind of a racing driver you should be within those tyre slip angles and with slicks that means more grip not less which means even faster lap times without PSM intervention. You should therefore not trigger the PSM unless on a very tight course. I don’t recall proper racing tracks being very tight, unless hill-climbs and I would not bring my turbo car on one of those as a preferred weapon of choice anyway. Can I see some lap times of yours for specific circuits please, so I can see how well you dust everyone with your modified properly aligned PSM free car? Then I will come over and see you as I am so curious to see you driving between 170-250km/h on different radius sweepers sideways with your PSM off. And if you do, you are donkey slow. Thanks.

PS. And for you to say that you are 2 seconds per lap faster with PSM off tells me all I need to know about your driving style and ability. Come back to me when you discover that smooth is the name of the game my friend. ;-)

PS2. And my MS story was just a metaphor on smooth driving and the pilot’s ability once at that level of racing.

 

Well you come into a forum full of experienced drivers and say we're not smooth because the PSM interupts without knowing all the details of what the cars have on them, or being an engineer or a racer yourself, yes, that is a joke.

Randy Pobst, Porsche factory driver and Speed GT driverwas recently at a Barber PCA event, he drove a Modified 997 Turbo, his own modded 996 Turbo, Al Nortons heavily modified Turbo, and several other peoples car and when I talked to everyone never did he once leave the PSM on in the car, and when talking to him he said he never would. I assume because it takes complete control out of his hands and he loves some power oversteer when he wants it.

Try cresting turn 4 at Barber Motorsports park with PSM off and even with the wheel STRAIGHT PSM cuts throttle. Because of the lightness in the car, it also applies brakes which is not beneficial ever. And have you ever considered that R compound tires have a greater slip angle threshold that 7%. At 7% a street tire is breaking loose, an R compound with major camber is not.

I'm not dumb enough to try and race someone on the ring considering it'd likely be my first time there, but I'd bet you if you are getting beat by 10 seconds with PSM on in the same vehicle by anyone you wont beat me.

 

And since you think PSM is so magical look at all the F1 times from this year compared to last, the average fast times are faster at every race so far, along with the fastest qualifying times.

So I suppose PSM is better than what F1 has that it can make your laps faster?

 

To come in at a much more moderate position...I think that for the 996tt, PSM is a boon ON AVERAGE. There are many places around local tracks where the PSM if left on will cut in, COMPLETELY without warrant. Say around the kink at VIR on the main straight with my hoosiers and my race setup. With PSM on, it would CUT POWER rounding the kink (and this is NOT an issue of smooth...the pavement undulates), causing the car to jerk and actually costing me 2-3 mph at the end of the straight...there are many places that when using certain tire/suspension combos, PSM is NOT helpful. That said, there are many places where it doesn't matter if I have PSM or not as it just will not come on. And before you say anything about just turning it off all the time for no reason because you are the uber driver, I will often race with PSM on and because to finish first, you must finish. That said, even I feel that the PSM on THIS car is far too strong at certain times.



And for what its worth...heavy isnt a pro, but he is a DAMN good driver!


EDIT: I dont know about some of you, but I feel the 996tt has a very "calculating" psm system...meaning that if I am trail-braking HARD and FAST into a medium speed corner and it feels the rear start to slip a bit faster than it likes, it assumes one doesnt know how to correct and does it for you FAR too soon. When one starts driving the car to limits (never said all limit, all the time), there is a time to turn it off (well, semi off as it is never completely off) as one cant learn to go to the next level with a nanny...take some looks at Leh Keen's videos or the likes and tell me that they dont look a bit on the edge at times...smooth is really a mantra more than a practice...one must be smooth yes, but to be truly BRILLIANT with a car, the smoothness is combined with a brutality that with any outside aid, will NEVER be achieved. FWIW

 

The fact of the matter is that Porsche can not make a system that can handle EVERY situation on every track.

I can enter the hairpin at Barber and carry the same speed on entry and with PSM on, it continuously cuts power, with it off I can rol right through the turn. I agree that in most turns if you can keep it off, you are being smoother, but that does not apply to ALL situations and to judge somebody's skills based on PSM cutting on is garbage.

 

First of all, for your info I am an engineer. Second of all, could you please read my posts properly before you continue to argue – at least give me that courtesy – after all I am giving it to you.

With the 10 second + I was referring to Schumi demolishing my time on a motorbike. Motorbike differences when racing (at amateur level) are much greater than in cars because rider skill can’t be as easily compensated for as in cars. How much do you think MS would beat you by on a proper race track in a car?

I will not get personal about this. I don't know you nor do you know me. I race motorbikes and I get my turbo to the limit very smoothly. PSM for me is a non-issue. If it lights up it simply tells me I wasn’t smooth enough. I keep it on and you have it off. Well, each to their own. However, Walter clearly said and I quote; for aggressive drivers system is not ideal and it may intrude a lot, if you are smooth however you won’t notice the system at work at all.

All I am saying is that perhaps you should try be smoother and perhaps you will be pleasantly surprised as you see those lap times come down.

PS. F1's are faster every year regardless of rules changing as they compensate by other means.

 

I think we should all go for a beer and argue there. :-)

 

If motorbike racing differs from car racing, and bikes donw have PSM, what is your point. Yes driver skill makes a difference but a pro driver can hate PSM as much as anyone.

I have all the respect for race drivers there is, but I doubt MS could run ALMS lap times in my car on sport cups. That's called having respect for the other guys that race too. And the cars. And DEFINITELY NOT even in the vicinity with PSM on.


And you are wrong about F1, since the onset of the V8 for the 2006 season the times were faster that first year of the V8. Because there was no limit on the developement of the engine until the end of the season. From 07-08 the only change has been no TC, guys are more inconsistent, but times have gone down.

Regardless of your abused Walter Rohrl quote, most race cars dont utilize TC, and certainly not a system that applies the brakes.

 

Ok can you please stop now. I give up. Yes you are right and yes I am dead wrong. I am glad that you are faster with PSM off rather then on. You are the God! Good for you. Can you please stop now and join a F1 team as they are probably dying to have you.

 

I agree with being 'smoother' would have helped but Streets of Willow is a tight track and I just don't have the traction in the rear. I had to feather the throttle quite a bit coming around the flat corner off the skid pad with the PSM off. If it was on, I suppose I could have feathered it just the same and not triggered the throttle control but I guess I don't know when the PSM will take over. With it off, I'm in control and can feel the slip and back off the throttle.

Now you gents go have a pint and play nice.