38D

I would say that if it feels lousy, then you are likely good enough to feel the limitations of the setup. Unless you are bringing a pro crews that is swapping out springs/shocks for every race, then your setup is a compromise. Even if you had a pro crew, each track setup is a compromise between the fast and slow, the bumpy and the smooth parts of the track. I think Larry is just at the point where he is going fast enough to notice the limitations of his setup.

JCP911S

IMHO, the car should feel beautiful at the limit... (of course this assumes that I have ever been at the "limit".... I do know I've been over it quite a few times).

The car should feel like it is gliding or floating...... almost like walking on ice... you can feel your feet slip a bit, but you are balanced and in no real danger of falling.... that is where the tires are at their maximum... you can almost feel the steering lighten up.... the car feels "up on its toes"

That's the perfecnt scenario....at that point more slip angle will simply make the tires scrub, and slow you down, and beat up the tires.

If the car is not set-up well... say the front gets there before the back....then you get understeer... if it is mild, then it is still faster to "straddle" that optimum point.. even if you are scrubbing the fronts a bit.... or use throttle steer to equal it out...

If it is really bad, then you just have to drive to the weakest end of the car, and get your *** kicked.

Since the car is almost never "perfectly" set up, you will be wrestling with it to some extent at the limit.... as the imbalance gets worse, the car feels more and more "crappy"

Bob Rouleau

Larry - great topic. Here's my take. When at the limit the car is not stable because we are playing catch and release. Tires have their maximum grip just as they begin to slide .. any more and the grip goes away fast. Assuming we can balance the car right at the limit of the slip angle of the tires in the first place, (what I call The Limit for any given set up - admitting that The Limit can be different for different set-ups) minor irregularities in the track surface force us to make constant corrections as we exceed The Limit and then gather the car back up. It is hard to keep this up for very long. This leads to my conclusion, "does the car feel like crap, or are we just not comfortable with the car when it is skating on The Limit"? Put another way, does my car feel like crap or do "I" feel like crap???

Best,

Adam Richman

Ahh, yes I know exactly what you mean. I think we are talking about the same sensation but it isn't a crap one, just an unnerving one - you are calling it hope you guessed it well, I am calling it a leap of faith and I betting your hope and my faith grow larger as the laps get quicker

38D, I think its entirely possible if not widely probable that one can know that a car feels lousy and know change is needed yet not know how to execute that. There was a thread on here way back where I said I thought one of the big drawbacks to the HPDE system is to always try fix the driver and not the car ... it might make for a highly adjustable driver but not a very saavy one at effecting good setup changes to the car. And then in contrast, if the change doesn't give the driver confidence, it doesn't matter how much it empiracly "improves" the car since a large part of feel is mental anyway. At least that's my way of looking at it.

APKhaos

Right on the money, Adam. Its surprising how many badly set up cars you can find at any HPDE or DE event, and all of them have had numerous instructors in them over time. Earlier this season, Mike Levitas spent a day riding right seat with a considerable number of Potomac drivers. Mike said later that he was really surprised at how many of the cars were really badly set up, and how the drivers were limited by their ability to manage their badly balanced cars. Just goes to demonstrate that pro drivers, and probably many of the guys on this board as well, have a well developed instinct for car setup. Most DE students, and maybe some DE instructors, probably don't.

phils87951

We dont have to catch and release at CMT Bob?
Nahhh

Very right though, how the driver feels is a major influence in the perception of speed.

Darren

I read a quote a few weeks ago that struck me:

"I couldn’t have driven one single lap more. I wouldn’t have liked to drive a single meter (3 feet) more with myself at the wheel at that speed"

From Jan Magnussen after his record? run at the Nurburgring in a Z06.

To me, that means that to drive the car at the limit, on that track, scared the crap out of him. If the car was totally comfortable at the limit, I'm sure he wouldn't be scared. But to drive the car as fast as a test driver does (btw, are these guys crazy or what???) I don't think it ever feels "under control"

Larry Herman

And here-in lies an important premise for this topic; in order to generate maximum grip from the tires, you have to work the car to make it produce that grip. This is done through braking, loading the front on turn-in and using the weight and rotation of the car to hookup the rear, get it pointed towards the apex, and out to trackout. You are not just driving the car, you are working the weight and balance in order to get the maximum grip from your tires. And you are teetering on that edge of grip. That is what makes cars feel "uncooperative" at their limits.

Many of you have mentioned setup. I think that my GT3 feels wonderfully balanced, and reacts predictably up to and even a little over the limit. It is just that the beautiful hooked up, "do anything I want it to do" feel that it has at 9/10ths morphs into a car that does not want to turn it, then wants to over-rotate, and then demands that you keep your foot in it, and countersteer in order to keep the back hooked up when you are at 10/10ths. I still submit to you that it is because you are at the limit of the tires, which defines the limit of the car.

With street tires, that edge of their grip is so wide that you can slide the heck out of your car, and really play around with the best slip angles comfortably. And the car feels like crap... The problem is that when you get to stiffer suspensions, and grippier tires, your edge gets really small, and the car get really tight and uncommunicative, and most people will not or cannot get those tires right on the edge consistently. And so they will drive them around below their limit, and think that everything feels fine. But if they are not sliding them, and they don't feel loose, then they are not at the limit.

brucegre

Absolutely true, and goes all the way back to Larry's original premise about the car feeling like crap at the limit. Sometimes, with the race car, we get the setup totally wrong and I have to deal with it for the whole race - that is no fun, but what else can you do but adapt?

Other times, the car is perfect, but the driver has the yips, and this is even worse - it's like I have no confidence in the car even though it's handling beatifully, so I cause it to do really weird things (you can't tiptoe around - the car needs to know who is in charge).

And then there are the days where it all comes together, and the car feels beautiful at the limit. It's that drift thing vs. that sliding thing. These are the days I live for.

So Larry, I agree, in general the car feels like crap at the limit, because we seldom get it perfect. But when we do,

Cheers,
Bruce

PS - the Big Belly Racing motto is STFUAD, a phrase our crew chief has been heard to utter once or twice, in general when one of us complains about the car during a race. Stands for Shut the F*** Up and Drive

brucegre

Larry, I guess we were posting at the same time. In your last post, you mention the behaviour of the car as you are just crossing the limit, and I think we're in violent agreement on this point.

For a particular track on a particular day, you can get a great setup that works pretty much everywhere on the track, and will react predictably in the spots where it is not ideal. But, when you put in a lap that is right on the edge, while the setup will help, every flaw and variation in the track will cause the car to dance a different way. When you are dancing right on the knife edge, the car really does feel like crap becase it's really hard to anticipate exactly what's coming next and there is a lot of reacting going on. It's why we can't run qualifying times lap after lap in a race - most of us can't keep the focus required to continually catch and adjust (Bob - I thought catch and release was a game we didn't tell our wives about ...) the car for more than one or two laps.

Cheers,
Bruce

Larry Herman

And so we back it down just a little bit, not much, and the car feels great, and we can drive lap after lap at that pace....but it's really not quite on the limit is it?

brucegre

Bingo!

But when I'm bench racing, I would never admit that.

Bruce

JackOlsen

Here's a gratuitous photo essay on the subject:

This weekend, I spent a lot of time on just this side of the limit. It felt great.





But then I had a front pair of brake pads go down to the metal, and I spent a little time on that side of the limit, which didn't feel so great.





Although I admit I felt better when the car stopped on just this side of the corner station.





'Happiness is not hitting concrete.'

JCP911S

Woah baby!... Better to be lucky than good, Jack? ... That was C L O S E!

JCP911S

Some thoughts:

1) HPDE really isn't intended to teach people to drive at "the limit"... IMHO either teach yourself, or go to racing school

2) First, you have to learn to drive the car to the limit as is.... then you can work on improving set-up... most of us have had suspensions break, tires lose air, etc during a race and have to adjust... so it is still up to the driver to use what the car has at that time.

3) Driving style greatly affects how a car responds.. two guys walk a tightrope...one guy goes across like a morning walk... the other falls off.... same tightrope... if I go in a bit too fast, or over-rotate the car, I will be struggling with the car the rest of the way through the turn.

4) For a given car and turn the "limit" is a sweet spot where the tires are at optimum slip angle... real world we are balancing steering, throttle, (and even brakes) holding the car in a band around that sweetspot... IMHO, the guy who can stay closest to that sweetspot witth the fewest adjustments to the car will be the better driver.

5) Ideally, the front and rear tires will be in that sweetspot at the same time... to the extent that the speed at which they find that sweetspot differs, then the car oversteers/understeers and the driver has to wrestle more and more with the car to keep it balanced