Tire size question

The biggest tire to run on a 9, on the street, would probably be a 275/60-15.
Do NOT put 325s on 9s, and do Not put 295s on 9s either. They will not run flat to the road, and will only burn the treads off prematurely.

I wonder if you are thinking straight. You paid to get those bigger tubs in there. You might as well fill them up now. Your engine needs more than 275s. And you could have put 275s in the factory tubs.