Biggest tire on a 640 (not M6)

[spdrcrgtr]

Whats the biggest tire side (front / back) that you guys are running on 20 inch wheels (20x9 F, 20x10 R)?

Ive been recommended:

245-35-20 F
285-30-20 R

I would like to go:

255-35-20 F
295-30-20 R

Would my sizes work on a lowered (H&Rs) 640 (not m6) without rubbing?

Thanks!