18 vs. 19 inch wheels for track days w/ S4 B8.5

[FilAlleva]

I have two sets of wheels, 18 and 19. (I currently keep winters on the 18's). I'm looking to switch to dedicated track tires. The question is which wheel size to commit to. There seem to be many more and cheaper tire options for 18 inch wheels. Going to 18's is appealing since I use the wheels in summer for my track days as change at the track but I'm also concerned about tire roll over with the higher profile.

Opinions? Wisdom? Knowledge?

[FilAlleva]

Talking to myself here by replying to my own thread - but since I did the some research I thought I'd share what I learned and where I landed.
First 18 vs. 19 is off the table since I opted for the Stoptech ST60 BBK so 19 is the minimum you can manage. There is a hugely informative website at https://www.enginebasics.com/Chassis...t%20Patch.html. Regarding roll over - this is also hugely complex. Tire construction suspension set-up, tire pressure all come into play. Depending on how much you care it seems the order in which you should worry about things is this - tire pressure hot (higher is better), tire construction (stiffer side walls), suspension. (Mostly in the order of expense and impact).