Im going to be doing a track day soon and i'm about out of tread on a set of rt-615's. This was going to make them perfect and it was gonna use up the last of their life. Bad news tho rain is in the forcast, so i'm thinking i will get a new set of tires before i go. I was wondering if anyone is running a smaller tire in the back vs the front. i'm not talking about anything crazy different just a 215/45/16 in the front and a 205/40/16 in the rear. I would idealy want two that were 45's but i cant seem to find the tires that i want in thoes sizes. anyhow. I have a little tire rub in the back which i was going to fix with a camber adjustmet but i don't know if i can get the car alignment changed before the track day. I did not have this problem when i was on the 205's. I don't even know if i'm a good enough of a driver yet to know if this would matter. I did notice a difference when i switched from 205 to 215, although the compounds were different. Any thoughts or suggestions would help. I'm either going to buy the Kumo XS or another set of rt-615's, couldn't find the dunlops in the sizes i could use.

This set up has nothing to do with the rain i was just cirious if anyone does this to balance the car. I have a set of 2 v rated pilots and 2 h rated pilots that i could use in the rain? would this be a better option? 96 gsr stock motor, coilovers, sway/strut bars, hawk pads, poly bushings, corner ballanced, some other odds and ends that really don't matter

 

From reading up on reviews and such the Kumho's are a lot better than the Azenis. I wouldn't worry about trying to tune your car with different size tires either. Just buy all the same sizes until you get more seat time. Different sizes would probably hurt more than help right now.

 

Kind of what i was figuring, any suggestion for the rain?? I can't budget in a dedicated set of rain tires, would the pilots be ok? I did an HPDE on the Kumo SPT's and they handled the wet great, anyone have any experience on the XS in the wet??

 

Sorry I can't help you there, I'm not sure about rain tires. To add to my previous comment however, you'll get the most out of the same size tires because you'll be able to rotate them and keep them all even. Rotating wider tires to the rear wouldn't be a good idea!

 

good point, didn't think that out that far ahead yet. ha

 

I agree, that's not a good reason to get different sizes. Get different size tires front and rear if you need them to accomplish something specific, not because that's the only size you can find one particular tire in.

If you want to transition from the Azenis RT-615 to the Kumho XS in the same size, I wouldn't be afraid to mix the two. (I'm aware of the dangers of using mismatched tires, but the two tires are similar enough in performance that it won't be crazy stupid.) Just keep matching tires on each axle, and be careful when exploring the limits of traction, especially in rain, as you may find a bit more under or oversteer than you're accustomed to.

Which Pilots?

I've been on SPTs on the track in the rain and they are indeed awesome. Although I haven't done so in the new XS yet, my guess is that it would be not as good as the SPT in rain, but not as bad as the Azenis, either.

 

I'm not exactly sure (pilot sport i think), they are a few years old 2 are V rated and 2 are H rated. but im happy to hear that you liked the SPT's in the wet too, makes me think i'm starting to learn a little, ha. That's kind of where i put the XS in the wet too. At this point i'm really thinking almost anything would be better than Azenis with 2/32nds.

 

Michelin makes a lot of tires with the "Pilot Sport" name on them, everything from track tires (Pilot Sport Cup) to all-seasons (Pilot Sport A/S) and a bunch of others. However, none of them are the supersticky "extreme performance summer tires" like the Azenis, XS, etc. For this reason, I would not mix any Pilot Sport tire with the Azenis.

There are two "maximum performance summer tires" in the Pilot Sport line, one is called simply the Pilot Sport and the other the Pilot Sport PS2. Both are good tires, and you could use them on the track, but again, I wouldn't mix them with the Azenis. By comparison with the Azenis, they don't grip as well on dry pavement, they grip better in rain, and they last longer - although those last two comparisons are also true of just about every street tire on the planet, LOL!

 

No i wasn't thinking about mixing brands, i was thinking about a narrower tire in the back to ballance the car. I didn't know if anyone did this. I don't think the pilots i have are a maximum performance tire, i'm pretty sure they are an MS all season. So i don't think they would be the greatest on the track. I ordered a pair of Kumo XS's, and will have to wait and see the forcast as we get closer to the day (may 8th pocono north course for 200 with cartct.com if anyone is interested, lots of track time) If anything i'll be able to let people know what the xs's do in the rain. I'll probably have to drag another set of tires with me if they are not the best. Hopefully not tho and the sun is out!