ColorChange

Brian:
I agree with you. You expect top notch drivers to be on the best line at the limit. G-sum and segment times will tell you if they are or not. Even F1 drivers are not all the time and work on different areas to improve. You are absolutely correct; a high g-sum does not guarantee you are quick (as I have said before). You need to combine segment times AND g-sum.

While I agree that it is immensely valuable to have a pro drop in your car and lay down pro data, (and as I have said before, I plan to do this), but I disagree that the limits will differ greatly. The limit of the vehicle is very dominated by the design and setup of the vehicle, not driver influence (tire traction is the fundamental limit). What I expect to see is him slam the car at 9.5+/10ths everywhere around the track and to show blistering lap (and segment) times. The smoothness (derivative of g-sum) should also be interesting to see. I hope to have this done in October at Putnam and of course I will share the data with the class.

Here is how I anticipate the conversation when I ask a pro to hop in. I will say I want to see his data so I can compare. If he is willing, I will ask if I can ride along. I will say drive it until your comfortable, then put down qualifying lap times. Push it as hard as you like. Dirt doesn’t bother me, bent sheet metal will. Have at it.

38D

I have to disagree with this. The limits of our various Porsche are very, very high, so I highly doubt that any of us really know where the limit is.

Here's a real world example. I run in the 2:17 range at Watkins Glen, which basically makes me one of the fastest guys in NNJR's black run group. Keith Peare, one of these faster club racers in the country, runs 2:01. Now, some of this is car (maybe 7-8 seconds worth) and some of this is driver ability (Keith is not human). I also have ridden with Keith at WG, and it was like being in a parallel universe...he was so much faster in the turns my brain couldn't even comprehend it. Point is, the limits of my car are higher than my brain can currently handle. So, unless you've had a top notch driver drive your car, or your name is Keith Peare/Ron/Kyle/etc., you really have no idea where the limit is.

DrJupeman

I remember the 50-50 at Watkins Glen from a few years back (call it the first Rennspot reunion). Keith was like 5th after two 962s, two 935s, and a 917. He was running a 2.7L (normally aspirated) 914!! "Not human" and "parallel universe" are accurate. I'm pretty sure Keith qualified with a 1:59 at that race.

Geo

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Tell that to every teammate Michael Schumacher has had in F1. Tell that to the F1 community. Ferarri has not always had the best car. MS was running away from the field driving a turd before they built the team they have today.

ColorChange

Guys, this seems to be another big misconception here. I am going to start another thread on car limits and drivers extracting the limit.

Why I am willing to do this (and suffer the personal attacks and anecdotal arguments that will assuredly follow), I'm not sure, but I will do it anyway.

Geo

I think most people here would agree. Where the misconception is you fail to recognize.

Yes, why?

Larry Herman

Boy, you just don't know how wrong you are. Driver input at and around the transition point has a major influence on the limit of the vehicle. Once you learn how to drive, if you ever do, you may just figure this out. No real flames intended, it's just the way it is and all of your theories and data acquistion crap can't change that.

iloveporsches

Guys, I'm pretty sure color is right on this latest issue. A car, set up a certain way, it going to have some mechanical limit. That doesn't mean everyone can reach that limit 99.999999% of the time like MS does though. He is a better driver, and therefore the "car" performs better, but its due to his limits, not the car's. If a car doesn't have limits, thats like saying MS can push any car as hard as an F1 just because.

Brian P

Sure, but then there is also the statement like "the pro's limits won't vary greatly from CC's". Unless CC is the next coming of Senna, I don't see how that could be true. I think CC thinks he is at the car's limits and there's no way a pro will be much higher. The only difference that he sees is the pro will be at that limit more often.

ColorChange

Brian, that is a good point. The reason I think a pro's limits will not be much higher than mine at Gingerman is because my car is set up fairly neutral and it is such a flat track that there are few tricky corners where his superior car balance can be demonstrated to a significant gain. Will a pro take a superior line and keep the car near the g-sum limit consistently and blow my lousy times away? Of course. This is not in dispute. I am only talking about the g-sum limit I have identified as 1.10, and that he will not be able to increase a lot IMO. I also now the absolute limits reasonably well from skid pad testing and since most of the corners are flat at Gingerman, the skid pad numbers transfer well.

Now, am I really sure of this? No. I haven’t had the opportunity to have a pro hop in yet but I hope I will at Putnam in a couple of weeks. Secondly, before the recent work (further lowering, adjusting shocks, sways, new tires, etc.) my car could pull a max g-sum of about 1.10 (it’s a little noisy signal). A pro driver might take that up another 0.1 but I think it will be very difficult to get it much higher than that but I don’t have direct data to confirm or deny my opinion.

Geo

I feel a haiku coming on......

DJ

Pros can't be faster
Car is limiting factor
Pulled out of my DAS.

Geo

Oh geez.... I can hardly type with Shiner Bock coming out my nose!

Z-man

Read Inner Speed Secrets by Ross Bently. Something that really stuck with me from that book is this: driving at the limits varies from driver to driver: IE: what I believe is MY 9/10ths is most likely a pro's 6/10ths. Also: as my ability increases, my driving at the limit also varies: what was my 9/10ths driving last season is now more likely my 7/10ths. In that case, the limit of the car didn't improve, but the limit of the driver did. (in a sense, a 'different' driver is driving the car!)

Color Change: I think a big assumption you have is that your 'driving at the limits' will not change - that your 10/10ths TODAY will be the same 10/10ths Tomorrow. That is simply not the case - the more seat time you have, the more you improve, and the further you can push your limits.

Step away from the DAS and ignore the g-sum numbers for a moment. You will then realize that there is a whole aspect of driving that indeed goes beyond the limits of g-sums and DAS systems. There are certain drivers (Like Senna, Donohue, & Shumi) that are able to put themselves into 'The ZONE.' While no one can go beyond the laws of physics, some drivers have the ability to bend them! Why do you think Mark Donohue's book is titled "The Unfair Advantage?" He knew the key to driving fast, and he knew it was more than just driving. That's what separates champions from winners...
I still cannot believe that you are putting so much emphasis on one single number: your all magical g-sum. (I also can't believe I'm still debating this issue with you as well!) Just go out there and learn to drive! I challenge you to turn off your DAS for at least one run and see how it feels.

-Z-man.

ScottMellor

DJ:
I'm actually crying.
May be your pithiest yet.