Hello from Antony Warmbold

[danon]

How many feel the difference - stiffness/softness.
The sensitive one has the advantage vs. the measurement rest.

[Coach 2]

I totally agree with your reasoning "Danon": The best one feel it.
But as "dimviii" said and "Steve Boyd" explained, 2mm on ABR, the difference this makes in handling of the car, most drivers feel.
Claiming: the driver (if he is skilled enough) that has or get, the best feeling with the surface in any rally, how much grip is available at any given time, etc. etc. becomes the winner of the rally. It is this that makes Loeb to the winner he is. And maybe also make Citroen to the winning team it is.
So as you say, "Danon" The sensitive one has the advantage.

[janvanvurpa]

Just imagine how hyper sensitive one should be in order to sense the 2 mm.
difference right away vs. ambiance, terrain and infinity of circumstances.

May be that's what make the difference between the good, the better and the best.

The best one feel it, the rest - measure it.

Good point. Racecar Engineer had a big giant interview with rally engineer Christian Loriaux some years back (right before they died in WRC, hmmmmmmm causation or correlation? You decide) and he was saying that it is very difficult to get solid data out of the drivers about how things were working on gravel because, in essence, good gravel drivers can 'drive around" or compensate for a lot of variable factors including "bad" or wrong set up....where on asphalt they can stick sensors all over and 'get good consistent data" and (he basically said several different and "polite" ways) we don't have to listen to the drivers ("because the systems are so complex they don't understand everything about suspension and diff maps etc"...

So knowing that subjective impressions are so variable, we have to have some numbers, not just spring rates, but damper rates, roll bars and we need numbers. I build lots of rally suspension, lots and evidently it works pretty good since guys are winning overall in regional events and even into top 5 in some Canadian national championship events--yes its all relative but only very subtile difference compared with very expensive brands. I use Bilstein stuff because they have a damper rating system for well forever where the damping force is expressed in a 1/10 notation of the N of force when they move the unit at a speed of 0,52m/s. and they are marked clearly.....it's really amazing how many guys have absolutely no idea at all what spring and damper setting are on their cars, just pure trust for the crew AND whatever the voice on the phone said.
Numbers are good.

[janvanvurpa]

I totally agree with your reasoning "Danon": The best one feel it.
But as "dimviii" said and "Steve Boyd" explained, 2mm on ABR, the difference this makes in handling of the car, most drivers feel.
Claiming: the driver (if he is skilled enough) that has or get, the best feeling with the surface in any rally, how much grip is available at any given time, etc. etc. becomes the winner of the rally. It is this that makes Loeb to the winner he is. And maybe also make Citroen to the winning team it is.
So as you say, "Danon" The sensitive one has the advantage.

Two ways to look at that, and one way I've seen is the "sensitive" are always using their too-refined sensitivty as reason to complain and moan...while the less sensitive maybe are concentrating on stomping on the gas more full gas than the other guy, and reacting of overcoming any slight subtile differences...best set up in the world doesn't help if the driver doesn't hold the gas down harder and longer---and then brake correctly..
The great Belgian moto-cross ace, 5 time 500 World Champion Roger DeCoster was once shaking his head and he said to me "If I have a good day and everything is set up right, I know i can beat Heikki (Heikki Mikkola from Finland, another giant), but if he has a good day, he can have one broken shock (back when bikes had 2 shocks), get off the "good" line and still beat me! he's an animal!"
Lucky for Roger his bikes were often 'everything right'...so 5x 500 World Champion...vs Mikkola 3 x in 500 and 1 time in 250.

always at least two ways to look at things. At least. and things look different when you're upside down hanging in the belts!

[Antony Warmbold]

If I remember correctly on the '04 car ARB's ranged from 25x3 (hardest to softest) to 25x2.5 ; 25x2 ; 25x1.5 ; 22x2.5 ; 22x2...

The ARB's were hollow tubes, not plain. ie: as I understood it, "25x2,5" meant "25mm" was the total diameter of the tube and "2,5mm" was the thickness of the tube wall. Somebody may have to corect me on this 'caus it's been a long time...The steps were 0.5mm of thickness. You could feel the differences in steps on gravel rather well compared to tarmac which was subtle to feel because there was a lot of grip. This car was always running very low to the ground, with little rolling anyways.

[Antony Warmbold]

I know that with the Mini RRC/WRC on testing with Snijers they often changed ARB's, also on shakedown before Ypres last year they tested a few possibilities. They tried 32, 30 and 28mm on the shakedown before Ypres last year, if I remember it right, sometimes changing in front or in back.
@Anthony: Do you know if for example Ø2mm make a real in how the car feels? Did you feel the difference if they changed these rather little things in tests?

our steps were different on the '04 focus, so it's difficult to relate to the 2mm steps of the mini that you write about. sorry.

[dimviii]

The ARB's were hollow tubes, not plain. ie: as I understood it, "25x2,5" meant "25mm" was the total diameter of the tube and "2,5mm" was the thickness of the tube wall. Somebody may have to corect me on this 'caus it's been a long time...

you are right Antony

[Coach 2]

Two ways to look at that, and one way I've seen is the "sensitive" are always using their too-refined sensitivty as reason to complain and moan...while the less sensitive maybe are concentrating on stomping on the gas more full gas than the other guy, and reacting of overcoming any slight subtile differences...best set up in the world doesn't help if the driver doesn't hold the gas down harder and longer---and then brake correctly..
The great Belgian moto-cross ace, 5 time 500 World Champion Roger DeCoster was once shaking his head and he said to me "If I have a good day and everything is set up right, I know i can beat Heikki (Heikki Mikkola from Finland, another giant), but if he has a good day, he can have one broken shock (back when bikes had 2 shocks), get off the "good" line and still beat me! he's an animal!"
Lucky for Roger his bikes were often 'everything right'...so 5x 500 World Champion...vs Mikkola 3 x in 500 and 1 time in 250.

always at least two ways to look at things. At least. and things look different when you're upside down hanging in the belts!

Correctly Jan. But I think you miss understood me. I meant sensitive to the surface, not too sensitive to the car setup.
But we can ask the question on to Antony.
What do you think was the hardest choice, to get the best feel for the surface?
Maybe even considering that you hardly got tested enough before each rally.

[janvanvurpa]

Correctly Jan. But I think you miss understood me. I meant sensitive to the surface, not too sensitive to the car setup.
But we can ask the question on to Antony.
What do you think was the hardest choice, to get the best feel for the surface?
Maybe even considering that you hardly got tested enough before each rally.

Not sure I understand the question.
Do you mean which surface is harder to get the car set up right?

Or which surface is hardest for the driver to feel the most comfortable with?

If you mean the car set right, my own experience is limited to loose surface and i say since the surface is itself a big giant variable in the equation depending on so many factors (where do you place the car? The clean line or? Where are you starting 3rd or 45th? so ruts and drive on rails or clean but maybe loose? dry or will it rain? A littl;e rain OK for just dust or really piss-rain? and on and on) I think gravel is easier... now this is speculation because tarmac is so "fremd für mich'' but it SEEMS that if we look at times over some years there are many many more guys that are fighting over onion skin thin differences on tarmac, so it seems that it must be easier to get the car right for MOST people..Or get it 98 or 98.7% right. And even at the highest level say position 11 to 6, that's probably good enough.

But not sure I got the question right....

[Coach 2]

Not sure I understand the question.

Do you mean which surface is harder to get the car set up right?

Or which surface is hardest for the driver to feel the most comfortable with?

If you mean the car set right, my own experience is limited to loose surface and i say since the surface is itself a big giant variable in the equation depending on so many factors (where do you place the car? The clean line or? Where are you starting 3rd or 45th? so ruts and drive on rails or clean but maybe loose? dry or will it rain? A littl;e rain OK for just dust or really piss-rain? and on and on) I think gravel is easier... now this is speculation because tarmac is so "fremd für mich'' but it SEEMS that if we look at times over some years there are many many more guys that are fighting over onion skin thin differences on tarmac, so it seems that it must be easier to get the car right for MOST people..Or get it 98 or 98.7% right. And even at the highest level say position 11 to 6, that's probably good enough.

But not sure I got the question right....

Thanks for the answer Janvan, but the question was meant for Antony W.
The question was meant as follows: If you have a test, normally it is also limited. Therefore, one must make choices under test / before start of the rally, perhaps in the rally. And before you see the result of these choices, which choice could be difficult to carry out / decide.
Sorry my English, and for Google's total lack of good suggestions.