If the wider tires came with an adjusted offset its not a problem. Think of it like adding tire to the inside not the outside, adding tire to the inside wont effect clipping.
The hackers can already widen the tires and it increases the size on the inside while the outside of the wheel stays in place. It would not take much to implement but they would have to reconnect the tires into the PP rating and This IMO will hurt online racing where tire selection is race conditions and strategy dependent, and adding tires back into pp would suck in my opinion making our online tires selections limited to everybody running the exact same tires, no more tire strategy... Its good tires and downforce have been pulled from PP ratings it opens them up to be tuned more personally by each driver.
Or get them to look wider but perform the same, I don't think that is a way to go, uncharacteristic of PD too.
They need only account for width etc. in the PP calculation. Compound can still be "free". That will result in a race to maximum width, which might look a bit silly and completely nullify the point of adjustable section unless there's a tradeoff.
Hmm. I can see that this is not an easy issue to fix.
Forgetting completely "free tyres" (except compound), they could stick to the "compound dictates peak lateral g" approach and scale the chassis / tyre grips accordingly as and when you scale the widths etc. They already do that for all the stock cars, they have fixed multipliers that make sure they show parity in lateral cornering ability, and longitudinal grip, for any given tyre compound. You would need to tweak those multipliers to account for changes in the tyres from stock only, excluding compound.
Maybe they could offer "regulated" and "unregulated" tyres. The former do the "peak grip" thing for racing parity, and the others react normally to changes for more relaxed environments.
An alternative is to offer fixed sizes of tyres for certain "classes" of racing. I think the faked peak grip would be more popular, beacuse players get to keep the physical look instead of being forced to use dorky-looking wheel / tyre combos.
I don't know if offering fixed tyres is mechanically equivalent to scaling grip levels on different shaped tyres. I expect the dynamics (as opposed to steady-state "peak" grip) would still be different, which is likely important. It's good on stock cars in a casual setting, beause it preserves some of the character of the original car, but in a race parity situation, perhaps not so much, I don't know.
Still not really "fixed".
My opinion: I don't think having lots of different fixed tyre sizes for different classes of car is workable, and I don't think letting some of the original character show through with the tyres is really a bad thing, either (the PP pros might correct me on that). So I vote regulated tyres by way of grip scaling for racing, and unregulated tyres for 1:1 modifications.
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