Would like to run 225/45x15 tires on my ITA Miata, but am having trouble locating a tire in that size that works well.

Avon makes one, but its a cantilever sidewall design is thus very heavy - extra 6 lbs per corner of unspring weight and rotating mass compared to a 205/50. Don't think thats a favorable tradeoff for a low-power, momentum car like the Miata.

Hoosier makes the R6 in that size, but their engineers don't recommend it for road course use on a 7" rim (apparently concerned about sidewall flex and heating). They said the 205/50 R6 would perform better because of less contact patch deformation under load at racing temps. However, I recently heard about a guy who was using the R6 225/45x15 on a 15x7 wheel on his ITS Bimmer successfully.

So, I'm confused.

Anybody got any relevant experience on this question?

Are ya' out there, Andy?