I checked in all tires calculator and this are the final recomendations:

Front: 245/45/18 for 7.5 rims
Rear: 275/40/18 or 265/40/18 for 8.5 rims

I did test 235/50/18 and 255/45/18. The feeling is good, but not for high speed driving. Clearance in the fenders were perfect.

Right now i have 225/45/18 and 245/45/18. They are very aggressive and in the front I have a huge gap.

Your recommendations please.

Thanks to all

 

I think a 275 may buldge a bit, sidewall wise.

 

I don't think 265/40/18 and 275/40/18 tires are recommended for 8.5" wide rims. You should have 9.0" wide at least for proper fitment.