I want to find alternatives to S02 for street and occasional track events for my AP1 wheels but I cant find 245s for the rear. Starspec, NT05, RE11, Kumho XS come in 225/50/16 for the fronts but they are not available in 245/45/16s. Anyone have other suggestions other than going 17s?

 

None of the current autocross-worthy tires come that wide. You can pray that the updated azenis 615k coming mext month will have that size, or the expanded star specs.
Otherwise, look for fuzion zri or some uber expensive continental (200 bucks for 245/45 R16)

 

Run a 225 square setup?

Or just get a set of used OEM 17"s for ~$400.

 

RA1. They're decent enough for summer street driving.

 

I thought the RA1s are discontinued.

 

Run stock sizes, or possibly 225's all around as CKit suggests.
For street/ocassional track (not competition) usage on street tires, on stock AP1 wheels, with stock AP1 suspension, I'd go with stock 205/55-16, 225/50-16 sizes. Star Specs are going to give you the best performance/$$$.

 

i just picked up a 225 square set-up of Ventus RS-3's to try out

 

Are you running a stock suspension? I wonder if it would be too loose running stock front sway bar w 225 squared.

 

I have 205 45 16 front 245 50 16 rear falken zeix 912s I love em just don't like the rear sidewalls so tall gives the car a little bit of a rake that I don't like

 

I am running stock suspension. haven't had a chance to try em out (too cold), but i'm thinking with the 01 front bar it should work out fine.