Yes exactly, these are very simple mechanics, but they are also the most fundamental.
TL;DR.... just further thought on same stuff:
I personally find base sliding friction parameter to be about right being about 55-65% of static base friction parameter. Having static bit higher and sliding slight lower than it maybe would be standard in sirmacing these days, except iRacing
But thats just based on feel and how cars perform comparing to what I can observe in real videos and even pictures (oh yes pictures too, as they are particularly good to see body roll and pitch and attitude of a car).
For people who are unfamiliar - TGM documentation from July 2013 refers to these most basic tire parameters like this:
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StaticBaseCoefficient = Base grip coefficient for static friction. Keep in mind this is essentially an absolute peak, perfect conditions, values over 3 are not uncommon for modern racing compounds. Static covers bristles that are static relative to the track surface. Keep in mind that during normal cornering, even toward the peak slip angle, various parts of the tyre contact patch are likely to be static. In other words, toward maximum speed, in a straight line, the majority of the contact patch will actually be static (but not necessarily entirely). Toward the other extreme in a large angle drift, it's probable that none of the contact patch is static (on the rear tyres), everything condition between will be a blend.
SlidingBaseCoefficient = Base grip coefficient for sliding friction, i.e. Something of a peak coefficient when the rubber is in a sliding state. See WLFParameters and Sliding(Adhesion/Micro/Macro)Curve entries below to vary the friction coefficient over different sliding speeds. It is important to remember that the nodes and resultant LD table primarily define at what point a bristle transitions between static and sliding, while the temporary bristle springs also have a say in this.
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Few things to note is that those are "absolute peak values". This is a bit unclear to me, because I don't know what are circumstances of peaking. For static I guess it is kind of understandable. But when the peaking friction of sliding happens ? The initiate moment tire begins to slide ? When sliding tire heats up to optimum temperature ? When sliding speed is near 0 ?
Lookup Data and bristle parameters also has significant meanign, as well as sliding speeds curves. I personally find abrasion curve to affect slidign behaviour quite a lot too, sudden extreme spike of abrasive wear. Haven't done specific tests to realyl prove that. But sudden extreme spike of abrasion curve will cause significant differecne in sliding behaviour and also will bring the flatspot significantly quicker.
The static curve parameter seems to only influence static friction if I understand this right:
StaticCurve = The static friction grip fraction relative to temperature curve in the format of (cold temperature, static grip multiplier @ aforementioned temperature, peak temperature, grip multiplier @ peak temperature, hot temperature and grip multiplier for said temperature). The values are blended together to form a wide smooth curve.
Thats a bit weird as I suppose heat would influence rubber sliding. But it seems like heat influence for sliding comes from "master curve" which is mentioned in
WLFParameters description, which is connected to sliding speed curves. Personally I like sliding speed curves as they are good way to alter slow vs high speeds corners stability and feel. But the WLF stuff is much less intuitive, you really must know hat you are doing there precisely lol
Aerodynamics in the mix complicates stuff further as they with first order influence to grip by altering loads has similar effects, also being speed relative like sliding, more speed more aero gains, but also more potential loss. In general it seems like very high speeds should be truly scary, as static friction will peak with highest downforce levels, and at the same time sliding friction will become more edgy, which should maybe then bring car close to base static friction, but the sliding friction will be near its lowest. At low speeds static friction wont be as high (with downforce car, opposite with lift car), but sliding friction will be closer to its peak, so it makes sense if at low speeds peak slip angles would be more safe, as transitioning from static to sliding wouldn't be as rough, but still we see can see some cars by aliens being thrown WRC style at slow turns, that is definitely a sign of sliding friction being overly high or/and static being too low.
