I am planning to buy used rota p45r wheels and this wheel is sick on my car(i guess).
The wheel size is 18x9.5 with 30mm offset.
I was thinking about buying falken fk-452 tires.
But I have no idea about tire sizes for the front and rear.
A friend on mine suggested 245/40/18 for front and 265/40/18 for rear.
So here is my question, what is the maximum tire width size for rear without cutting any part of the z(fender I guess)? I think 275/40/18 would work without any cutting. Please give me any recommendation!

 

Did you get 9.5 +30 front and rear. If so you can run 295/35 rear and 275/35 fronts no prob.

 

295/35 on a 9.5" wheel? Sounds a little too wide for that wheel.

 

275/35 is a solid choice.. I run that size right now but my car is completely slammed.

 

Never mind. I thought this was important.

 

+1^^^^

 

 

If you aren't doing any competions where wide tires will gain you an advantage then you would be fine with a 275/35/18 for a 18x9.5 wheel. I've run the a 245/40/18 F and a 275/40/18 R and felt the rear sidewall was too tall compared to the front.

You could go bigger than 275 with out rear fittment issues but you would be beyond what is "recommended" for a 9.5 width rim.

You can use these TireRack.com spec sheets to determine what tires fit with your rims. This link shows the specs for the Michelin PS2 (most overrated tire in the world but used here as an example because they make a lot of larger width sizes in 18). You'll find a column on this spec sheet labeled "Rim Width Range". Find the row for the tire size you are looking for and you'll see if you rims are in the recommended range for the tire size.