I have searched the forum and it seems most have been talking about using a 40 series tire on their 17" wheel. I have a set of 17x8 wheels and was hoping someone had some knowledge of anyone using a 50 or even 55 series tire tire. Any feedback is appreciated.

I'm using a 45 series 18 inch tire in the back of my 67. It is plenty tall, don't believe I've seen any 50 series.

I have 255/40 r17 on mine on the back. I would say there is plenty of room for a 50 series on mine. I have 5.5 inch backspace and a 9.5 inch rim. Also it has a 12bolt out of a 69 so its a little wider and has hotchkis one inch lower springs. If I ran an 8 inch wheel there is a ton of wheel well space for a taller tire.

I have 255/45/17's (Nitto 555's) on the back of my Camaro. The 255/45's are 25.95" tall with a 4.5" sidewall, a 235/60/15 is 26" tall with a 5.5" sidewall for comparison. The 255/45/17 has about a 1/2" wider section width with an 1 1/2" wider tread width than the 235/60/15...

A 255/50/17 is about 27" tall and you get a 5" sidewall but the section width almost a half inch more than the 45 series. The tread width is almost an inch less though...

I used the 235/60/15 for comparison as it's a very common size 15" tire on Camaros and Chevelles.

These sites can help you figure out tire sizes.
http://www.tirerack.com/tires/SearchTires.jsp

http://www.nittotire.com/tires_555.asp

I've seen 35,40,45,50,55,60,and 70 series 17" tires. Just depends on how tall a tire your car can handle. About 31" is about the max most untubbed A-bodies can handle.
Two tires than work very well on the rear are 255/50/17's and 275/50/17's.
Not sure I follow you on the 255/50 being narrower than a 255/45. Aspect ratio shouldn't change the tread width,only the sidewall height.

Hi Clint - I had to think it out a bit but per Tire Racks "specs" a 255/50/17 in an 8" wide wheel and has a 10.4" section width and a 8.2" tread width. A 255/45/17 has a 10" section width and a 9.1" tread width.

The tire with more sidewall has more overall width (sidewall to sidewall) than the low profile tire. The low profile has a straighter sidewall and larger contact patch (tread width).

Originally posted by DjD:
Hi Clint - I had to think it out a bit but per Tire Racks "specs" a 255/50/17 in an 8" wide wheel and has a 10.4" section width and a 8.2" tread width. A 255/45/17 has a 10" section width and a 9.1" tread width.
The tire with more sidewall has more overall width (sidewall to sidewall) than the low profile tire. The low profile has a straighter sidewall and larger contact patch (tread width). I think that's a typo on Tire Rack's site. I'm guessing that the 255/50's tread width should be around 9.4",not 8.2". A taller tire has more footprint on the ground at a given point,also.

When you do the math 255mm = 10.04" (mm divide by 25.4). That is the overall width of the tire (width at the widest point) which falls along the sidewall though and is not the tread width. Both 255's (45 and 50 series) fall right in within .04" of that. The lower profile tire will have the wider contact patch (tread width) by design. I believe this is done because teh shorter sidewalls flex less and and allow for a more squared off corner from sidewall to tread surface. The taller sidewalls flex would cause the tread surface to break down too fast so by design the sidewall tapers into the tread more.


Now a taller tire (27") has a larger circumfrence than a smaller tire (say 26") so it will have more contact front to back or in the direction of the roll which may equate to more sq inches of contact.