The Mother Lode- Road Amercia

[George Main]

As no one seems to be talking about it, does that mean no ones going?

One the greatest racetracks in America, and no discussion on it? Nobody going to the runoffs this year?
We had had Atlanta for many years, then Mid Ohio for several more, and now we are going to a track that will make you think your at the Nurenburgring. And no discussion? Does everyone have this track figured out? You must cause not much discussion. That one test day going to sort it out? Let me know when you take the kink flat out, cause I want to have a lawn chair and popcorn in hand to watch! Or if your class can, the carousel flat (it's not the line that counts)...maybe not the popcorn but the lawn chair for the amount of time spent in it.
How about the missing Micthell bridge? Gone! Is it flat?
New pavement on the outside of one, eight.? Can you go there?

Three miles of straightaway, with one mile of corners, are you ready? Got enough horsepower to climb out of 14 and draft somebody into one? Got brakes and hind sight to find the braking zone for 5? Will you run wing or without it...?

BTW, if you don't have suspension sensors, you'll wonder why your braking don't work in someplaces and why you can't remove downforce in others (when you could)
As no one seems to be talking about it, does that mean no ones going?

[Bill Bonow]

...that will make you think your at the Nurenburgring.

Isn't that where the Nazi war crimes trials took place?

Der Nurburgring - Nordschleife and no, running Road America never made me think I was at the Green Hell, not even at tiny bit.

[Stan Clayton]

As no one seems to be talking about it, does that mean no ones going?

No...it means we aren't talking about how we're going to tackle it.

[George Main]

Isn't that where the Nazi war crimes trials took place?

Der Nurburgring - Nordschleife and no, running Road America never made me think I was at the Green Hell, not even at tiny bit.

There's only one Nordschleife, green hell as you put it. My comments and comparison was tongue in cheek....

The biggest decision most will have to make, if you have wings or adjustable aero will be to run with more or with less. The best place to make that decision IMO will be how the car responds to the change in the carousel. Theres a "rise" in the first half of it and slightly downhill in the second half of it. Less or more wing will show if it's a benefit or not, half way from entry to this rise, with the rise causing it's own problem (with less wing most often) and then the second half presents it's own problems, as there is a slight off camber to it, (downhill).
If you have suspension sensors, pay perticular attention to the rear suspension, as there are a succession of bumps in the first half that will throw a wrench into your aero program.
There have been several track records set with opposite routes of thinking in aero. Though the majority of them have been set with less aero (three miles of straightaway) but to do so, making the car balanced and maintaining mechanical grip in the carousel is a double edged sword. IMHO

[Marshall Mauney]

Let me know when you take the kink flat out, cause I want to have a lawn chair and popcorn in hand to watch!

I took it flat today (have the data to prove it), and I still came in 5th in class. Once you can take it flat, you still have to figure out how to scrub the least amount of speed - that's the real challenge.

Or if your class can, the carousel flat (it's not the line that counts)...maybe not the popcorn but the lawn chair for the amount of time spent in it.

Now, if you could show me how to tak the carousel flat in an FE, I'm all ears!

New pavement on the outside of one, eight.? Can you go there?

Only if you don't mind coming in with loose suspension bolts after every session. It's nice added runoff area for when you need it, but the rumble bumps are enough to keep you from gaining anything (at least it seems that way to me and my meager experience).

Got brakes and hind sight to find the braking zone for 5? Will you run wing or without it...?

5 is easy: wait until you know you probably can't make the corner, go one marker more, then brake hard, downshift and turn. You have enough runoff that a mistake here is just really embarassing (because everyone having lunch on the hill will be watching), not expensive.

[dc]

Let me know when you take the kink flat out, cause I want to have a lawn chair and popcorn in hand to watch! Or if your class can, the carousel flat (it's not the line that counts)...maybe not the popcorn but the lawn chair for the amount of time spent in it.

If I'm not mistaken, just about every class represented on this board takes the Kink flat out. I don't know if anyone does the Carousel flat out, though.

[Allen_W]

Like Marshall, I have data to show we took the kink flat this weekend. Unfortunately, as the world turns, this was not the same weekend I could take the carousel flat--my fronts were toast, and the understeer in the carousel (and six and fourteen and thirteen and one and seven and so one) pretty much scotched that thought.

As to RA, it is my favorite track. It is not as god-awful challenging as Grattan, but I doubt I will ever have it half figured out. I think, on the other hand, that Tim Kautz has it pretty much figured in a Ford. I love to watch him on this track . . . for the millisecond I get to watch when he blows by me.

If I'm not mistaken, just about every class represented on this board takes the Kink flat out. I don't know if anyone does the Carousel flat out, though.

[mazda17]

I regularly did the carousel flat out in my FE at the June Sprints, just had to lift the last few laps of the race as the tires lost grip.
Scott

[iamuwere]

I regularly did the carousel flat out in my FE at the June Sprints, just had to lift the last few laps of the race as the tires lost grip.
Scott

Flat out as in no braking before the corner or lift going into it or flat out once the car sets?

jim

[mazda17]

Flat out as in exit turn 8 flat out and no braking or lifting at all until the entry of Canada corner.

[Allen_W]

Flat out as in exit turn 8 flat out and no braking or lifting at all until the entry of Canada corner.

Exactly. That is the thing.

[Marshall Mauney]

I regularly did the carousel flat out in my FE at the June Sprints, just had to lift the last few laps of the race as the tires lost grip.
Scott

I won't question this given your laptimes, but how the @#$% can you do that?

I can't keep the front tires sticking. Halfway through the carousel, it just gives up and wants to go out into the marbles. Of course, shortly after I lift to put grip on the front, it starts to stick again and I feel too slow.....

[Allen_W]

I won't question this given your laptimes, but how the @#$% can you do that?

I can't keep the front tires sticking. Halfway through the carousel, it just gives up and wants to go out into the marbles. Of course, shortly after I lift to put grip on the front, it starts to stick again and I feel too slow.....

Sadly Marshall, even in a lowly FF I know this feeling all too well--marbles and grass beyond OR lift a bit . . . sigh.

[Rennie Clayton]

If I'm not mistaken, just about every class represented on this board takes the Kink flat out. I don't know if anyone does the Carousel flat out, though.

Guilty as charged... flat from the exit of 8 to the entry of Canada Corner.


Cheers,
Rennie

[mazda17]

It's a secret

[rickb99]

....I don't know if anyone does the Carousel flat out, though.

Hmmm, I watched a LOT of the videos from the June Sprints. I didn't see any body doing the Carousel 'FLAT OUT'.. Yes, no braking but feathering the throttle most of the way around.

Where's a video of a FLAT OUT acceleration through the Carousel??? Maybe in an FV or perhaps an FF (maybe).

[Matt King]

Hmmm, I watched a LOT of the videos from the June Sprints. I didn't see any body doing the Carousel 'FLAT OUT'.. Yes, no braking but feathering the throttle most of the way around.

Where's a video of a FLAT OUT acceleration through the Carousel??? Maybe in an FV or perhaps an FF (maybe).

The only way to prove it is to show us a throttle trace! Definitely can be done in a FV.

[mazda17]

Hmmm, I watched a LOT of the videos from the June Sprints. I didn't see any body doing the Carousel 'FLAT OUT'.. Yes, no braking but feathering the throttle most of the way around.

Where's a video of a FLAT OUT acceleration through the Carousel??? Maybe in an FV or perhaps an FF (maybe).

Come to the Hippi Racing paddock at the Runoffs and I will show you a flat out throttle trace in an FE all the way from turn 8 to Canada Corner.

[JRMarchand]

oh yeah, flat carousel is done all the time, i learned watching the pro's on tv, watch the "pro" line, a good line to me means that you are almost in the "marble zone"on entry, Road America and the Chicago Region have the best safety crew , they go to work fast!! today a Pro Mazda came out of 7 very squirly , hit the right wall on exit and the car exploded in front of us, i hope the driver is ok, local yellow for turn 7 for 3 laps, two safety trucks and crew cleaned up the mess with cars zooming by, i was hoping for a full course, it was a little too much, god bless.

the bridge is not there anymore, it is true flatness from curb to curb, i think turn one is never talked about, T1 is mean too. jrm

[mark defer]

any top running FC takes the carousel totally flat.
for me, i don't want even a hint of understeer there. i prefer to have the car set up so it has a hint of oversteer that i can control with the steering. if you can't take it flat, it will definitely show in your lap times.

mark d

[George Main]

Hmmm, I watched a LOT of the videos from the June Sprints. I didn't see any body doing the Carousel 'FLAT OUT'.. Yes, no braking but feathering the throttle most of the way around.

Where's a video of a FLAT OUT acceleration through the Carousel??? Maybe in an FV or perhaps an FF (maybe).

A Formula Atllantic. flat in the Carousel, will "sound" as though it's rolling out of the throttle (with the pedal to the wood) due to the G loading scrubing speed off the car, same happens with most cars.

Take that same atlantic car, and peel off aero, so much that the carosel becomes difficult to stay flat. In 1996 we removed Patrick Carpentier's rear upper element (RT41) completely in practice, we went 1.4 seconds slower than we had before. But the advantages in straight line speed were there, and we "discovered" a key suspension movement that removing the rear wing had caused. We tried it again in qualifying with the new suspensions settings, and destroyed the track record.
Both the carousel and even the Kink were challenging to remain flat in both, as the speed difference was so much higher.
If wasn't for suspension data, where the handling faults were found that were caused by removing the wing, we would not have tried it again in qualifying.

Doug is correct, most, if not all cars at this website should be flat in both the carousel and especially the kink. Though as you "push" the envelope of the aero, it will become more and more difficult to do so. IMHO

[George Main]

For those that haven't been to this track before, if it rains, make sure you at least go around the track a few times so that you figure out the puddles and streams that will occur. The risk of starting a race in the rain and not having been around it in the rain, will catch you by surprise in a few places here:

Turn 1, the last "rise" that blocks your vision of the braking area for one, can develope huge puddles and deep sometimes, just after the rise. Not the best place for a "surprise".

Turn 2 entry, turn 5 braking, 6 just before entry, 7 through out, mitchell corner entry all develop streams.

Canada, and turn 8 tend to have a lot of puddles, Canada in the braking zone, 8 apex and out.

From the Kink to exiting Canada, the track is surrounded and "covered" with trees and can stay wet even though the rest of the track has dried.

Just like Atlanta, it is also possible for it to rain on one side of the track and be completely dry on the other.IMHO

[George Main]

any top running FC takes the carousel totally flat.
for me, i don't want even a hint of understeer there. i prefer to have the car set up so it has a hint of oversteer that i can control with the steering. if you can't take it flat, it will definitely show in your lap times.

mark d

Which conditiion is faster? Which condition will have more confidence? My mentor and good friend, Bob Lobenberg once got into this discussion on U/S vs O/S (they were talking about turn 1 at Atlanta) and whether the "loose/O/S is fast" statement is really all that's made up to be. His response was that, for him, once you have a little O/S, are you going to press harder the next time around, thus creating more O/S? Will you have the confidence to do so? Bob seems to think that a little U/S is far more confident to the driver when dealing with very fast corners, as you can still get to a neutral state, by pushing harder and rotating the car, knowing that the U/S will happen. With O/S, it is only bravery that separates whether you will go quicker the next lap.
When I've coached drivers on corners that we know are flat out, but the driver isn't able to do so yet, having a little U/S "built" into the car is a much safer way to get someone to go flat.

[mark defer]

yes, but if you've already worked up to being flat out, there is no pushing to go farther next time thru the corner. and since we seem to loose front grip first as the tires wear, i don't want to start out with an understeer that's only going to get worse. do that and you won't be flat out by the end of the race.

mark d

[andyllc]

In general terms I would absolutely prefer a little U/S compared to O/S. However in the carousel, it seems if your car understeers it just gets worse and worse and just wants to plow off the track, that is one turn where I would prefer a touch of oversteer if I had to choose one.

[George Main]

yes, but if you've already worked up to being flat out, there is no pushing to go farther next time thru the corner. and since we seem to loose front grip first as the tires wear, i don't want to start out with an understeer that's only going to get worse. do that and you won't be flat out by the end of the race.

mark d

"since we seem to loose front grip first as the tires wear"


Is this because of the tire design? or because of how you have setup the car? Only makes sense that if you can't change the tire personality (compound choice,pressures, camber, growth, etc.) then I can see your point.
Even in an FE, has some things you can do to change the character of how the tire wears. Though sometimes it requires thinking outside of the box.....

[Rennie Clayton]

Which conditiion is faster? Which condition will have more confidence? My mentor and good friend, Bob Lobenberg once got into this discussion on U/S vs O/S (they were talking about turn 1 at Atlanta) and whether the "loose/O/S is fast" statement is really all that's made up to be. His response was that, for him, once you have a little O/S, are you going to press harder the next time around, thus creating more O/S? Will you have the confidence to do so? Bob seems to think that a little U/S is far more confident to the driver when dealing with very fast corners, as you can still get to a neutral state, by pushing harder and rotating the car, knowing that the U/S will happen. With O/S, it is only bravery that separates whether you will go quicker the next lap.
When I've coached drivers on corners that we know are flat out, but the driver isn't able to do so yet, having a little U/S "built" into the car is a much safer way to get someone to go flat.

Two "which" questions to kick it off, and yet one short: which driver?

All of the stability baselines and car behaviours which you (correctly) indicate are "modifiable" by the driver are all predicated on the tendencies of the driver to behave a certain way behind the wheel. This is why particular setups do not work well for particular drivers, and also why some drivers adapt well to a multitude of setups (although that driver is rare indeed). I suspect you know this though.

The converse of what you've written above is also true, in terms of setup direction - a driver may induce understeer at will to a car which otherwise exhibits oversteer, by virtue of changing his / her technique. No bravery needed, just a change in technique.

I am being careful not to try to answer the question of "which is quicker", because I believe it depends on the combination of setup and driver tendencies. Is there a theoretical fastest? Almost certainly. Would the car be drivable by a human with that setup? Different story.


Cheers,
Rennie

[George Main]

Two "which" questions to kick it off, and yet one short: which driver?

All of the stability baselines and car behaviours which you (correctly) indicate are "modifiable" by the driver are all predicated on the tendencies of the driver to behave a certain way behind the wheel. This is why particular setups do not work well for particular drivers, and also why some drivers adapt well to a multitude of setups (although that driver is rare indeed). I suspect you know this though.

The converse of what you've written above is also true, in terms of setup direction - a driver may induce understeer at will to a car which otherwise exhibits oversteer, by virtue of changing his / her technique. No bravery needed, just a change in technique.

I am being careful not to try to answer the question of "which is quicker", because I believe it depends on the combination of setup and driver tendencies. Is there a theoretical fastest? Almost certainly. Would the car be drivable by a human with that setup? Different story.


Cheers,
Rennie

The quickest way is a neutral car all the way through, and the most confident. Though the handling differences I'm describing are "which end will give up first".
If your flat and your slightly O/S'ing, and your drafting a car into and through the carousel, that O/S will become a lot of O/S. Having the front go into a slight U/S when pushed is a little more confident to the driver,( depends on who you are) and can be managed much easier (you can rotate the car) to get passed the U/S. With O/S, your kinda stuck with the situation, and the length of rolling back the throttle to keep the car on the track vs a "quick" lift in and out (enough to rotate) to correct a U/S condition.
What happens if the tracks get slippery due to oil (can you say "darn GT1 guys, how much oil do they carry anyways?), different types of rubber or moisture
Which handling condition is more manageable in changing track conditions?

[Brian.Novak]

Come to the Hippi Racing paddock at the Runoffs and I will show you a flat out throttle trace in an FE all the way from turn 8 to Canada Corner.

Yup! Can be done, although I don't think my car handles it as well as yours!

Could do it in the F500 also.

[Marshall Mauney]

Yup! Can be done, although I don't think my car handles it as well as yours!

[Rennie Clayton]

Which handling condition is more manageable in changing track conditions?

We talking about making the car go fast, or making it comfortable to drive?


Cheers,
Rennie

[George Main]

We talking about making the car go fast, or making it comfortable to drive?


Cheers,
Rennie

"Tricking" the car to do something will, more often than not, also trick the driver at some point.

A well balanced, confident car that is easy to drive fast with a capable driver will win out most of the time over a car that has been "tricked" into it's speed.
A small example of "tricking" the car? pre-load and packers.... sometimes it works, sometimes it doesn't. The balanced easy to drive car always works with less surprises. In the heat of battle, which driver will make the least amount of mistakes? Which car will get pushed to 11/10ths more often?
In my mind, if the driver is confident in his/her car, pushing the limits of it is much easier than pushing a car that will suddenly do something that is unexpected..
IMHO

[Rennie Clayton]

George,

Who said anything about "tricks"? Not I...

For the record, spring preload is diabolical, and I've never been a fan of packers for a variety of reasons. I even go so far as to find coil springs distasteful because one is constantly fiddling with getting spring slack just right, or your droop may vary from side to side... just a mess to deal with sometimes. Anyway, for most drivers, giving them a nice docile car in the 3-5hz range with a moderate forward bias in ride rate, a narrow forward bias on roll rate, and overshooting critical damping by, what, 50% on an aero car will give them something to chew on for hours. It will be quite easy to drive, very consistent up to 98% of the ultimate limit, docile and linear when pushed over the limit, and assuming all the mechanical bells & whistles have been properly looked after, it won't give any real surprises. Adjust to the peculiarities of the track without going overboard, and more often than not, you end up with a race winner on your hands.

Perhaps we should distinguish here between steady state and dynamic state? Neutral is desirable in steady state, and we are both in agreement there. Better to have a car which breaks loose at both ends simultaneously. Some drivers are comfortable with a car that oversteers; most are not. What are your thoughts on how the car reacts in dynamic state? In general, I am talking about stability factors, and I do not refer to behaviours which are inconsistent or surprising. For instance, I presume you are an advocate of rearward weight bias, although that is inherently unstable from a dynamic response perspective.


Cheers,
Rennie

[JRMarchand]

George

I much rather have a car that is comfortable or neutral, than a car that is designed to understeer or O/S halfway through the race. ??? I mean how can a car go from understeering to oversteering in just 13 laps?? maybe the tires go away? the driver gets tired or thinks about other things? really how can i make my car o/s at the start and then have a few laps when it understeers, i mean really.

I hear the Nascar guys talking about the car getting tight or loose at the end of a 50 lap run, thats just tires eh. you can always induce the two conditions above with less/more steering input, point of entry & speed

[George Main]

Sorry, been very busy in the last two weeks...

George,

Who said anything about "tricks"? Not I...

No, you didn't imply any tricks, I did, as I have seen many who in the course of setting up a car attempt to "trick it" to do something. In some cases, as with an FE or Sports "rambo" where the springs, ARBs, and tires etc., are set Or Formula Mazda, where selections are also limited. Tricking the car has, once again become a "mode" of setup that some regularly go down this path in "most situations" rather than just a few times.

For the record, spring preload is diabolical, and I've never been a fan of packers for a variety of reasons. I even go so far as to find coil springs distasteful because one is constantly fiddling with getting spring slack just right, or your droop may vary from side to side... just a mess to deal with sometimes.

Agreed, though there have been instances were it's worked, but most involve flat racetracks that have the bumps in the right places...

Anyway, for most drivers, giving them a nice docile car in the 3-5hz range with a moderate forward bias in ride rate, a narrow forward bias on roll rate, and overshooting critical damping by, what, 50% on an aero car will give them something to chew on for hours. It will be quite easy to drive, very consistent up to 98% of the ultimate limit, docile and linear when pushed over the limit, and assuming all the mechanical bells & whistles have been properly looked after, it won't give any real surprises. Adjust to the peculiarities of the track without going overboard, and more often than not, you end up with a race winner on your hands.

Agreed, though don't agree on the overdampening, except in very special cases,. IE- a Porsche cup car can respond very well to this, but has to do with engine location and the "little" chance of jacking the car down.

Perhaps we should distinguish here between steady state and dynamic state? Neutral is desirable in steady state, and we are both in agreement there. Better to have a car which breaks loose at both ends simultaneously. Some drivers are comfortable with a car that oversteers; most are not. What are your thoughts on how the car reacts in dynamic state? In general, I am talking about stability factors, and I do not refer to behaviours which are inconsistent or surprising. For instance, I presume you are an advocate of rearward weight bias, although that is inherently unstable from a dynamic response perspective.

Interesting, don't you think? That when a driver debriefs, the steady state is the least likely to be brought up and the dynamic movements are the ones most complained of? (usually the instances where he saved his rear end) Yet in setup we try to achieve the longest possible steady state conditiions and reduce and control the dynamic movements. Sometimes in controling dynamic movements we reduce the steady state, one way by overdampening (some use shocks to control all aspects of handling, IMHO, a mistake) or flooding the car with aero to mask a problem, IMHO, also a mistake.
A shocks greatest importance and effect happens mostly in such low percentage in one corner of a track (initial turn in and power on exit) and though the shocks do effect the car in other parts of the corner, the importance of them should only be "heightened" after you already have a very balanced car, irrespective of the shock adjustments.
A great experiment is to spend a test day with a set of dead shocks (low enough pressure that low speed control is not functioning) and purely attack the handling through your spring, bar, camber, caster, rake, air pressure and geometric adjustments. If the car has aero (wings), removing or greatly reducing their effect, that also can allow a focus purely on mechanical grip. (Though not removing tunnels or diffusers)
Though not a route to a well setup car, the learning process of this increases the dynamic movements that may be masked or "patched" by other elements that aren't as important to achieving a well balanced car and "targets" the effect that the shocks and the wings have on the car when they are brought individual back into the package...

An added effect of this kind of testing, is that the driver relates to each of the changes and what he has to change (driving wise) as all the dynamic movements are greatly increased and once they become smaller again are much easier realized in their individual effect on the car.

[George Main]

George

I much rather have a car that is comfortable or neutral, than a car that is designed to understeer or O/S halfway through the race. ??? I mean how can a car go from understeering to oversteering in just 13 laps?? maybe the tires go away? the driver gets tired or thinks about other things? really how can i make my car o/s at the start and then have a few laps when it understeers, i mean really.

It is possible to have a neutral car which is setup so that when pressed too hard (11 tenths?) will go into an understeering condition rather than the more "natural" oversteering condition of a rear engine car.
I haven't mentioned anything about a car going from under steer to over steer, and in fact won't know how to achieve that unless it was the natural life span of the tires.

I hear the Nascar guys talking about the car getting tight or loose at the end of a 50 lap run, thats just tires eh. you can always induce the two conditions above with less/more steering input, point of entry & speed

Not exactly what I or Bob L. meant either. If the choice was a car that will go into over steer (many believe this is fastest) when pressed VS a car that will go into under steer when pressed.
A neutral car is the goal, and is fastest and the most comfortable to drive. Though the discussion is when a neutral car is pressed even harder than 10 tenths. The chances of a rear engine car remaining neutral are very low and will tend to head into over steer. That is unless the car has been set in such a way that the car will under steer (from a neutral state)

Though how do you turn an over steering car to begin with, into a car that is understeering or neutral.... without slowing down (much less throttle) at any point when at ten tenths throughout a corner?
My point is that when you take a corner at 10ths and the car is setup to have an over steer, you as a driver are not going to go any quicker on the next lap by pushing the O/S envelope. Though if it was a slight understeer instead, the level of confidence is higher that you can achieve a neutral car even when pushing the car harder and faster into the corner.

[TimW]

Though how do you turn an over steering car to begin with, into a car that is understeering or neutral.... without slowing down (much less throttle) at any point when at ten tenths throughout a corner?

My point is that when you take a corner at 10ths and the car is setup to have an over steer, you as a driver are not going to go any quicker on the next lap by pushing the O/S envelope. Though if it was a slight understeer instead, the level of confidence is higher that you can achieve a neutral car even when pushing the car harder and faster into the corner.

So, I think this is more of a social engineering phenomena than an engineering phenomena, which is fundamentally a lot of what a race engineer is responsible to do. However, it doesn't seem to work universally with all drivers this way in my experience. Since a neutral car is so hard if ever to attain, you must choose which side of neutral you're willing to live with. While a car with understeer can (though not always) instill confidence, at a place like the speedway it just scrubs speed and slows you down. Sure if feels safer to be able turn the wheel more sometimes but with the wall coming at you quickly it may also not give a driver confidence to be more aggressive.

Its been my experience that a car that is controllably loose, meaning that the driver can correct the condition without varying throttle (and he has confidence the car reacts in this condition linearly repeatedly) that you will get to the next corner quicker simple because the deceleration due to tire scrub of non directional wheels will be less at small yaw angles and the fact the driver hasn't tried to rotate the car with the throttle once entered. This of course does not go to the extremes of 'rallying' a car around a corner as the Doc Hudson turn right to go left method simply creates too much scrub from the rear tires going sideways.

[George Main]

So, I think this is more of a social engineering phenomena than an engineering phenomena, which is fundamentally a lot of what a race engineer is responsible to do. However, it doesn't seem to work universally with all drivers this way in my experience. Since a neutral car is so hard if ever to attain, you must choose which side of neutral you're willing to live with. While a car with understeer can (though not always) instill confidence, at a place like the speedway it just scrubs speed and slows you down. Sure if feels safer to be able turn the wheel more sometimes but with the wall coming at you quickly it may also not give a driver confidence to be more aggressive.

Its been my experience that a car that is controllably loose, meaning that the driver can correct the condition without varying throttle (and he has confidence the car reacts in this condition linearly repeatedly) that you will get to the next corner quicker simple because the deceleration due to tire scrub of non directional wheels will be less at small yaw angles and the fact the driver hasn't tried to rotate the car with the throttle once entered. This of course does not go to the extremes of 'rallying' a car around a corner as the Doc Hudson turn right to go left method simply creates too much scrub from the rear tires going sideways.

Actually I believe it is bit of both social and engineering phenomena to have a successfull racing program.

An Oval is a different animal all together. When you start to involve banking especially. All dynamic movements are greatly enhanced and even small handling problems are big ones. The setups for an oval are so far removed from a road race car that a comparison isn't even fair.

Its been my experience that a car that is controllably loose, meaning that the driver can correct the condition without varying throttle (and he has confidence the car reacts in this condition linearly repeatedly) that you will get to the next corner quicker simple because the deceleration due to tire scrub of non directional wheels will be less at small yaw angles and the fact the driver hasn't tried to rotate the car with the throttle once entered. This of course does not go to the extremes of 'rallying' a car around a corner as the Doc Hudson turn right to go left method simply creates too much scrub from the rear tires going sideways.

Without argument, though only with respect to the car maintaining grip within it's slip angles and not above them. I guess that's what you mean by "Doc Hudson".
It is unavoidable to have a car not achieve a larger slip angle on the rear tires over the front on a full throttle exit of the corner (a very well setup car). So having said that, adding any oversteer as result of "over driving" the exit is less desirable and slower than the car acquiring a slight understeer as the result. The U/S condition takes less time and thus less time loss to correct as a driver. And is more likely to be managed with more confidence and most importantly, can easily be attempted lap after lap, and keep the car on the track.

(as a note, so we don't fall in a semantics discussion, In my view, oversteer/understeer are conditions outside of the tire's achievable slip angle on that end of the car).

The biggest difference I have seen in driving styles is in the driver's knowledge of "what exactly" car rotation is and whether the driver has acquired a few techniques of doing so vs. those that don't/can't rotate correctly and need the car to do it for them. This technique is critical for dealing with understeer, in a manner that keeps the lap time loss from being too great.....IMHO

[mark defer]

george,
a question.
i know that you were a pretty accomplished data guy working in FA with DSTP.
but have you ever spent much seat time in a formula car?
just wondering.


mark d

[Rennie Clayton]

No, you didn't imply any tricks, I did, as I have seen many who in the course of setting up a car attempt to "trick it" to do something. In some cases, as with an FE or Sports "rambo" where the springs, ARBs, and tires etc., are set Or Formula Mazda, where selections are also limited. Tricking the car has, once again become a "mode" of setup that some regularly go down this path in "most situations" rather than just a few times.

There is no substitute for fundamentals.

Agreed, though don't agree on the overdampening, except in very special cases,. IE- a Porsche cup car can respond very well to this, but has to do with engine location and the "little" chance of jacking the car down.

Overshooting critical damping does not directly translate to overdamped, necessarily. Depends on smoothness of circuit, mostly. Also note that I did specifically call out "aero" cars - no way in hell would I take this approach with a FF, for instance. More like 0.3-0.5 critical damping, if that. This is one of those areas where a compromise is necessary between your budget and how fast you want to go - "optimum" damping rates are not the same for ride, roll, or pitch control. So you either need to find a good middle ground damping rate that gives overall good performance, or throw a lot more dampers and linkages on your car to achieve good balance in isolation.

Interesting, don't you think? That when a driver debriefs, the steady state is the least likely to be brought up and the dynamic movements are the ones most complained of?

Spend some quality time as a driver at the sharp end of the grid, and you'll understand why.

A great experiment ... [trimmed] ... An added effect of this kind of testing, is that the driver relates to each of the changes and what he has to change (driving wise) as all the dynamic movements are greatly increased and once they become smaller again are much easier realized in their individual effect on the car.

This is how I learned to drive and setup cars. I learned to drive on dirt ovals in the midwest - 4 cylinder factory stock cars at first, straight out of the junkyard and stripped down of all non-essentials. I'd fill up the gas tank and pound around for hours on the local track. Stop, make a change - any change - and go back out for a half dozen more laps. Literally spent most of the summer doing this before my first season - damn near won my first race, too, despite starting from the "rookie pole", AKA back row. Since then I've gotten a bit more educated and put some formal engineering practice behind it, but the lessons still apply.

Though how do you turn an over steering car to begin with, into a car that is understeering or neutral.... without slowing down (much less throttle) at any point when at ten tenths throughout a corner?

For this, I direct you to your own follow-on. Technique applies heavily in dealing with oversteer, and likely to a greater degree even than dealing with understeer:

The biggest difference I have seen in driving styles is in the driver's knowledge of "what exactly" car rotation is and whether the driver has acquired a few techniques of doing so vs. those that don't/can't rotate correctly and need the car to do it for them. This technique is critical for dealing with understeer, in a manner that keeps the lap time loss from being too great.....IMHO

Cheers,
Rennie