Best gripping strip tire for a stock 15x7 rim?

[t-topflyer]

Would like to put a set of better gripping rear tires on stock 15x7 vector rims. Would like to keep height of the tire as close to stock 26" as possible. What's the best gripping/widest size tire I can safely put on one of these rims?

 

[t-topflyer]

Found it, nevermind 275/50/15