Hi everyone:
The ultimate test of an ICR car setup is basically how fast a good
driver can go in that setup. The feel of the car's handling in the
turns is a good indication of how good the setup is, but tire temps
are the measurable indication of the performance of the car, and that
is the question I want to pose to icr racers who have good experience
setting up cars.
1. Will best grip be achieved when the temps are uniform across the tire?
(The manual gives the optimum temp for each tire compound, e.g.,
240 for soft.) So, does that mean that the best grip will be if the temps
of the tire are 240/240/240 for I/M/O ? ) or is leaning the tire in
gives better grip ?
2. If uniform is better, then will the THEORITICAL IDEAL setup produce
tire temps of 240 (for soft, 250 for mediuam, etc) uniformly
across all FOUR tires ?? (I know you can't usually get all tires
that hot, and that's why I say theoritical).
3. Any ideas about how to raise the tire temp (other then lowering
pressure ) perhaps by suspension tuning ??
Thanks for your comments.
========================================================================
Mohamad Shaheen The best thrill in racing is to rocket
Plasma Engineering down the straightaway, break at the last
University of Illinois moment, down shift and dive for the apex.
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Quoted text (12 lines)
> Hi everyone: > The ultimate test of an ICR car setup is basically how fast a good > driver can go in that setup. The feel of the car's handling in the > turns is a good indication of how good the setup is, but tire temps > are the measurable indication of the performance of the car, and that > is the question I want to pose to icr racers who have good experience > setting up cars. > 1. Will best grip be achieved when the temps are uniform across the tire? > (The manual gives the optimum temp for each tire compound, e.g., > 240 for soft.) So, does that mean that the best grip will be if the temps > of the tire are 240/240/240 for I/M/O ? ) or is leaning the tire in > gives better grip ?|> 1. Will best grip be achieved when the temps are uniform across the tire?
|> (The manual gives the optimum temp for each tire compound, e.g.,
|> 240 for soft.) So, does that mean that the best grip will be if the temps
|> of the tire are 240/240/240 for I/M/O ? ) or is leaning the tire in
|> gives better grip ?
The idea is to have even temps across the tire in the turns. Uneven temps
show that one part of the tire is being over worked and another part is
under worked. You probably already know this but the simplest way to
think about adjusting for even temps is, tire pressure adjusts the middle
temp relative to the side temps and wheel camber adjusts the side temps
relative to each other.
|> 2. If uniform is better, then will the THEORITICAL IDEAL setup produce
|> tire temps of 240 (for soft, 250 for mediuam, etc) uniformly
|> across all FOUR tires ?? (I know you can't usually get all tires
|> that hot, and that's why I say theoritical).
I don't know because I haven't completely read the books I have on the
subject. I would guess this is correct.
|> 3. Any ideas about how to raise the tire temp (other then lowering
|> pressure ) perhaps by suspension tuning ??
Raising the temp is accomplished by transferring more weight to that
tire by increasing the spring rate at that tire. This is done by
increasing the spring rate, making that shock harder, increasing
the roll bar stiffness on that end of the car, and/or increasing the
wing on that end of the car. I haven't had a chance to play with ICR
enough yet to try this out. I have a hard enough time just getting
around the Portland track without falling off. And I have over 2,000
miles on the real track! :-/
--
Mentor Graphics Corporation (Wilsonville, OR)
87 VW GTI 16V 85 VW Golf #32 - Conference Production H
>Raising the temp is accomplished by transferring more weight to that
>tire by increasing the spring rate at that tire. This is done by
>increasing the spring rate, making that shock harder, increasing
>the roll bar stiffness on that end of the car, and/or increasing the
>wing on that end of the car. I haven't had a chance to play with ICR
>enough yet to try this out.
It doesn't work that way in Indycar - first of all there is no spring
rate to be adjusted. Shock firmness can cause anything heating or cooling
of a certain tire, mostly because it lets teh tire get more or less
grip (more squeel = less grip = more temp = less speed). On the
other hand, stiffer shocks make the car's steering more responsive.
The anti roll-bars do about the same thing: softer=more grip, less temps
but poor handling. And don't worry about the manual - it doesn't
really work the way they describe it.
The secret to even tire temps lies in finding a good balance between
downforce, shockrate, rollbars, stagger, camber and tire compound and
pressure, all of which has to also match your driving style. in Indycar,
it is usually a good idea to avoid ANY kind of tire squeel, as it
indicates speed being shaved off and tires heating up more than needed.
It boils down to a lot of test miles - 2000 on one track is about
right.
Peter
