Here's a dumb question since I don't understand wheel/tire sizes.

So the size of the 18's on a G37 is:

225/50 18

My current vehicle (pont g6) has:

225/50 17

So how much more "low profile" are the 18's, compared to my current 17s? Is the difference just one inch 18 vs 17 lol

Basically, the only thing holding me back from the coupe are the 18s, and knowing full well, my *** is going to hit a pot hole, or several over the course of ownership.

 

They aren't low profile at all. As you see the sidewalk thickness is 50. I hate the beef on my 18s and can't wait until I get some new wheels.

 

What constitutes low profile then?

Less than 50?
Less than 40?

 

I don't know the exact def, but in my eyes 50 is def not low profile, unless you consider your tires are low profile now?

 

No, but my current tires are 17s.

 

Depends who you talk to. If you talk to a baby boomer, he will tell you that 60 series is low profile. 20 years ago a very popular "big rim low profile" size was 205-55-16. Nowadays 16's are like 14's in the 80's. 18's are now becoming standard and 50 series are definitely NOT low profile. At least not by today's standards.

 

The 50 is the "aspect ratio", and in this case 50% of 225 is the height of your tire sidewall. So, that's about 11 cm. The aspect ratio itself, be it 40 or 50 doesn't make your tire low profile. Tires which are 280/50 and 225/50 have the same aspect ratio, but the wall height is different. Again, there's no consensus on what exactly is low for a side wall height, but the 18s on the G are definitely not. I wouldn't worry much about it. Many people have the G37S, with 19" rims and even less side wall height compared to the 18" rims. I would be careful to avoid potholes regardless of what rim size I had!

 

Of course, but hitting pot holes is almost inevitable, and my current 17s have been pretty absorbent. The only wheel damage I've done was when I ran on it flat, because I'm a moron.

 

Well, where I live, the roads aren't the best, and I've had my share of potholes, but nothing so bad that it bent the rim. What kinda giant potholes do you have going over there???? :P

 

LOL seriously where do you live? I drive to LA every single day, and no problem. I actually plan on going with some 20s in the future...God help me ahaha

 

Your rim size isn't the issue. Both tires you mention are 225/50, which means they have the exact same sidewall height. The only difference is what's stuck inside those sidewalls (17s vs 18s).

 

haha well in Chicago you can have a -20 degree day followed by a 50 degree day and that just destroys the roads.

That and I'm just probably a bad driver lol

 

The sidewalls are the same height but the 18's would handle the pot holes better since their diameter is 1 inch more than the 17's.

You can compare for yourself...

 

I know nothing about this stuff. I have stock wheels on my '09 x. The roads in Cleveland are in horrible shape. Would a different size wheel or tire size look more aggressive, without causing me problems?