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[Thunderguts]

I'm running a square setup with 17x8 wheels with a 45 mm offset. I'd like to get more grip, but keep the neutrality of a square setup with the ability to rotate. I don't have much room between the strut and tire wall in the front, but I'm not rubbing on the fender at all with 225/45 tires right now.

Unfortunately there are very few 235 mm tires in that size, but the Dunlop Direzza is a candidate and it might still clear the strut. When I compared the specs to the 225 mm Pilot Sport 4s, something seems off.

Notice that I gain almost an inch more tire tread on the ground, but the section width is the same. Given that the 225s were measured on a 7.5" wheel and the 235s were on an 8.5" wheel, this seems odd. I'm running an 8" wheel so I guess I would fall in the middle.

How can the section width be the same with almost an inch more tread width? Do the Direzzas have an almost square profile while the Michelins taper a lot at the end? It appears this would be a great way to get a lot more rubber on the ground without rubbing on my struts. Am I missing something?

[tracer bullet]

I don't know these tires but I can say for sure that you're onto something that does exist, tires being different real life sizes when showing as the same widths on paper.

Back when I had my Eclipse, which had an upper arm that curved / arched over the tire, Some brands would clear it where others would hit it. All tires were the same "size".

It happened here as well, a user compared heights of old and new tires from different companies that had the same size on the sidewall.

[iminhell1]

I'm on a 235/40-17 (9.7" and 8.7") on a 17x9 rim up front. But I'm on a Federal RS-RR and they run WIDE. It's a tight fit.

If you're close to the strut, run a spacer (don't forget to add to the bolt length to compensate, or just swap to studs and be done).


Also if you go with the Dunlops, see if you can find the XL load rating.

[drunkenup]

How can the section width be the same with almost an inch more tread width? Do the Direzzas have an almost square profile while the Michelins taper a lot at the end?

^that is why, most tires in the extreme summer category are going to be this way versus a max performance summer tire like PS4S. But something to consider is that the Direzza will last for about 12k street miles where the PS4S will go twice as far, while being way quieter. Though, the Z3 is acceptable as far as noise goes with how padded up our cars are.

[Thunderguts]

I'm not expecting to get much life from them and that's fine. Rotating will give me a little more life than I would otherwise get out of them. With that much more tread on the pavement, I should notice an improvement in overall grip which is worth a little tire wear.

[tsk94]

Originally Posted by Thunderguts

How can the section width be the same with almost an inch more tread width? Do the Direzzas have an almost square profile while the Michelins taper a lot at the end? It appears this would be a great way to get a lot more rubber on the ground without rubbing on my struts. Am I missing something?

That's exactly it. Each tire will vary depending on it's design. While the section width might be the same, the tread width is what you should be looking at to determine actual contact patch. Section width is worth noting for fitment, but don't look at section width to see how much tire contact a specific tire will have.