Transient tyre characteristic

[speedsense]

Not to mention, as I said, that I can have a control construction and two different compounds.. providing very close levels of grip.. but driving completely differently.

Exactly...my point.. and this isn't gray at all,at least to the driver or the person plotting out the setup to make it work.

To me and the driver, the transient behavior of the tire, is the limiting factor of not only how the car is driven but also how it's setup. If either one goes in a different direction, purely because of a tire (and most the time it is the reason) then it a fundamental problem which is directly related to the tire.


And Tom, I greatly respect your point of view and your sharing your knowledge with it, though we may not agree on certain points. With certain companies I've cemented relationships with tire people whom I seek out for their tire advice, but in the end the decisions made on the choices of tire and the setup that followed that lies ultimately with the driver. I never forget the reasons why I'm told something whether it's because of the legal constraints or company policies that contour the advice. (One of which I always seek out in your company) Nor do I have a choice of a better bias or a better radial, at the racetrack, unless it's available. Often it's only two or one, darn spec tires.
Outside of compound choices, it's still bias or radial...which one do you want?

I would love nothing more than to be proven wrong, so that I wouldn't have to change my thinking and setup according to a type of tire. But until I can bolt on a bias or a radial that makes little to no difference in either the setup or the driver technique, I am unconvinced that there's no difference that it is only just a "gray" area.

Maybe we should be discussing this transient behavior?

[ubrben]

In my experience the transient response of the tyre is so fast that control moment tends to dominate the driver's opinion on the response of the car as a whole.

I would like to agree with you (& certainly work under that assumption). It doesn't stop damper people trying to sell "magic", however. Have you heard of the Ohlins patented "high frequency function piston" which, according to the blurb, "gives a short, low dampened stroke" (aka "backlash", so far as I have been able to "see")?

Interestingly, perhaps, I first heard about the phenomenon a (long) time ago, when John Miles introduced backlash in a set of front dampers by accident, and "transformed" the handling characteristics of a racing Esprit he was working on. It was he, BTW, that talked about tyres "buckling".

Having said all that, I believe firmly that backlash (accidental or deliberate) is not the correct solution.

I think we both agree on that based on recent experience Backlash in the damper is really bad for driver perception of the platform he's got.

On the other points. I think Tom's correct; belted or non-belted is probably the correct binary difference rather than bias or radial. Most belted race tyres aren't true radials. They may have ply angles less than even 70 degrees. The lower you go on ply angle with a belted tyre the harder it is for the belt to do it's job.

Ben

[speedsense]

Have you or Tom ever set up a race car that was your responsibility, I mean the results of the driver and the car were directly related to your changes of springs, shocks, geometry setting and such? Or have you always just made sure the shoes fit the foot? Just curious...

[Jersey Tom]

Have you or Tom ever set up a race car that was your responsibility, I mean the results of the driver and the car were directly related to your changes of springs, shocks, geometry setting and such? Or have you always just made sure the shoes fit the foot? Just curious...

Yes, though admittedly not professionally. All amateur.

Plus, plenty of vehicle sim work (professionally).

[ubrben]

Have you or Tom ever set up a race car that was your responsibility, I mean the results of the driver and the car were directly related to your changes of springs, shocks, geometry setting and such? Or have you always just made sure the shoes fit the foot? Just curious...

Done FSAE and I don't mean to suggest that compares with real racing. Part of the current project I'm involved in has modified the tyre and suggested setup changes for existing tyres using moment method simulation.

I'm not coming on here pretending that I could do a good a job as someone with your experience, just that I know tyres pretty well and you made some gross generalisations that I didn't think added a lot, that's all.

Ben