I have a 2004 Touring 350z the Potenza tire that came with them are 225/50r17 front and 235/50r17. I thought that the 17 meant that I have 17 inch rims but when i measured them they are 18 inch rims, so what does the 17 stand for in the xxx/50r17.
Thanks, E

 

Yes my 350 is a auto, but i took a measuring tape out and it did measure 18inches across.
hummmmmmmmm

 

Were you drinking while you were taking those measurements? If not, you should have been.

 

I swear I just went out and measured again and the rims are just over 18inches. will someone who has 225/50r17 front and235/50r17 back go measure and post PLEASE.
Thanks, E

 

I dont think its possible to put 17 inch tire on an 18 inch rim...

 

A 17 inch wheel is 17 inches across the tire bead seating surface. The lip of the wheel extends beyond that, so if you measure the wheel flange to flange, it will measure more than 17 inches.

Example: I have 18 inch wheels on my roadster. They measure 19.5 inches flange to flange.

 

I'm going to use the "flange" method to measure my "johnson" from now on.