Knowing the sidewalls is important. Talk to your manufacturer - which means you're going to need to go to some trouble figuring out who and where to find them - the guy at the tire store will be of only a little help vs. none at all. I sense their stiffness on turn in and then through halfway to apex.....after that, other variables are too much in play for me to think about sidewalls. If you're running a fairly low profile tire, stiffness is going to be a little harder to judge.
Do you take your tire pressures in pit lane? You do use a pyrometer on the tires immediately in pit lane after a session......right? Many will say you need a pyrometer that has a probe you stick into the tire such that you are measuring temp just below surface......and they are correct at that third decimal place way of thinking. I use a 'point & shoot' IR pyrometer because it's faster and a one man operation can jump out and do it quickly on pit lane......knowing temps on a relative basis points me in the right direction.

 

Tires are an important part of your suspension system. If you're looking for absolute top performance, then you would need to adjust suspension settings whenever you switch tire brands. Be consistent with tire pressure as well.

 

Yep. There's a huge difference in sidewall stiffness between tire models and this significantly effects ride quality and chassis response. The difference between a 35 series sidewall and 30 can also be large. This then combines with the compound changes. The Cup2 will cause more rollover of both the chassis and the tire carcass. Evoras have a lot of road feel and you can tell the difference easily. In the 200TW race world, I prefer the RE-71 to the A052 not because of overall grip, but because of increased feel through the sidewall. I know what the contact is doing (or is about to do) so I can drive faster with fewer big "moments".

 

Ahh that’s good context. When you say increased feel, does the mean when coming out of a corner that the steering wheel comes does not come back to center as much?

 

The way the sidewall flexes affects how the contact patch deforms, how the tire takes up grip, how force and slip angle are related, etc. This affects steering response, how much grip the car feels like it has, etc.