Really, to be honest, a 225 is the max you'll want to put on it. Anything more is just going to look stupid, handle floppy, and be more expensive than necessary. Even a 225 is probably too big. A smaller, stickier tire is gonna be your best bet if you want grip.
I know this is a kouki, but this guy has 245's on his s14 SE wheels. They're monstrous. And not in a good way.
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