For a staggered 245 8.5" Front and 275 9.5" Rear setup should the sidewall size be the same 35 front and rear or 35 front and 30 for the rear? I've heard different things.

This is for a sedan and will have a drop on Eibach pro-kit as well.


Also if you have Lexion 503s, Maya RT5's, or Volk GT-C's on a sedan could you please post a picture? All I can find are coupe pictures when searching.

just like the stock you need to keep the aspect ratio same. so for 19's 35. if you go 35 front 30 back the rear tires will be smaller then the front.

I run 245/35R19 front and 285/35R19 reaar on Volk Racing GT-C RMC. Sorry I don't have any close up photos and mine is a coupe. Good luck man.

I have opted for 35 front and rear. I am quite happy with the result.

You don't have to have the same series tires front and rear. You won't necessarily have a narrower/thinner sideway if you have a lower series rear tire compared to the front tire. Let me explain. 245/40R18 tire size. The first set of numbers (245) represents the width of the tire in millimeters. The second set of numbers (40) is the thickness of the sidewall as a percentage of the tire's width, thus called Aspect Ratio. Lastly, the third set of numbers (19) is the rim diameter. Plus sizing a 2004 G35 up 2 sizes is not the best example, but the difference in the sidewall thickness between the front and rear is very minimal. A good example, however, is the Lamborghini Murcielago. In stock trim, it comes with 245/35R18 front and 335/30R18 rear. The second set of numbers in the rear tires (30) is smaller than those of the front (35). If you convert these two numbers to the sidewall sizes in millimeters you have 85.75 mm in the front and 100.50 mm in the rear. So basically, the sidewall size is a percentage of the tire's width. There you go. You don't have to have the same series tires front and rear. The best thing to do is to consult a local tuner shop or call places like Tires.com or TireRack.com if one is unsure about the tire sizes to use.

Very good size selection as they are very close to the overall diameter of the OE tire size.

Thanks guys.

Anyone seen the chrome Lexion 503's on a sedan? I think that is my top choice right now. The Maya rt5's are a little pricey for me I think.

for tire sizes that fit this application same series tires do apply. Stock 225/45/18 and 245/45/18 have a diameter of 26.0 and 26.7 inches. A 245/35/19 and 275/35/19 combo has a diameter of 25.8 and 26.6 inches, a little smaller then stock. If you went with a 275/30/19 in the rear you would only have a diameter of 25.5 inches which is smaller then the front. You would need to run a 325/30/19 in the rear to get a diameter of 26.7, which would not fit without major modifications.

I have made a spreadsheet that does the tire size caluculation for you. Just enter the width in mm, sidewall in percentage and wheel size in inches (who comes up with this stuff?) and the other info will be calculated. It will compare to the OEM tire size and show the difference in circumference. I left my calculations there as an example.