Just got a set of 17" rims for my 94 Z28 the other day from a friend. Rims are good but he threw in the tires as well that are about bald, so I'm going to replace them. The size on the sidewall says 315/35Z/R17 as the title says but I've found from looking around on here that 275/40/17 is the correct size for them. Is there a disadvantage to having this size tire on the 17s compared to the 275/40s? I like how they look but I value how the tires will perform more. Thanks. Also noting that these came off of his 97 Z28.

 

How wide are the rims? A 315 tire needs a 10" to 12" wide rim. A 275 needs an 8.5" to 9.5" wide rim.

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Rim width requirements are set by the tire manufacturers. Not all manufacturers have the same range of wheel widths for the same tire size. Looking at Tire Rack, they list three 315/35-17 street tires. Two of them recommend 10.5" - 12.5" and one recommends 10.0" - 12.0".

For the 275/40-17 size, most tire manufacturers recommend a wheel width in the range of 9.0" - 11.0"

Putting a wide tire in a wheel that is too narrow will reduce the contact patch, and cause excessive flexing of sidewall and tread, causing heat build up and faster deterioration of the tire carcass.

 

They will work, but balloon out. As for danger, I've experienced nothing but I have sumitomos which run narrower than my nitto 555s. I'm Swapping back to 275s onto the 17x9s. Besides that tough look it gives, the only other plus is braking is better because of the extra meat.

For the rear tires go for it, but stick with 275s up front unless you got a smoking deal on them, then sure run them, it won't hurt anything.