The above is the only point on which I'm still waffling when it comes to 225 vs 235. I do like the look and added protection of a meatier tire, but I'm on 225s now and not sure how much the steering feel would change. Could someone please school me a bit on what difference I would feel in DD/spirited mountain road driving? Or real world experiences between the two sizes? Would like to make a purchase soon as my Konigs are on the way (but could probably wait a month if ya'll think there will be some super Black Friday sale?).
Well I might take back everything I said simply because the Indy 500 tire seems to be pretty damn narrow! Look at the pics above your post, if that's 245/40-18 and it's still *just* square, there's no way a 225 or 235 is going to be anywhere near square to protect the rim, so that's a non-issue considering just those 2 sizes.
Steering feel increases with a bit of stretch because you have less sidewall flex because it's already "tensioned". You're not going to have the tire flexing outside of the rim in corners which can feel loose and sloppy. Steering would feel more direct and accurate because you're not dealing with as much tire flex. Are you going to notice it? Maybe, but because this tire seems to have a narrow profile a 225/40 might look more stretched than you want.
The two wheels on the right are 18x8.5 with 225/40-18 Pilot Cup 2 tires, and they don't look *that* stretched compared to a 245/40-18 in the post above.
This is a set of 225/40-18 Indy 500s on an 18x8! And look at the sidewall: