Max tire size - 68 dart
I can tell you that 255-60-15 will fit with correct offset steel wheel .. i had stockton build me wheels ..but i need clarification .. 275-60-15 WILL "NOT " fit with stock suspension ?? thanks
Correct, 275's won't fit on a Dart/scamp/valiant with the stock spring locations. At least not any I've seen. Now, to confuse the issue further, 275's will fit on a Duster, Demon, Dart Sport and Barracuda with stock spring locations. But not a Dart.
As for the 255's, I know it's been done but not everyone can do it. Something important to note is that not all 255's have the same section width. Actual tire measurements for a given size vary by tire manufacturer. I've seen 255's that are listed as having a 10.3" section width and 255's that are listed as having a 10" section width. On my car the 10" section width would fit fine with no mods at all. The 10.3", on the other hand, might not. It would be super tight even if the backspace was perfect. Whether they rubbed or not would depend on the car, ride height, spring rate etc. One of those deals where everything might be fine until someone jumps in the backseat for a ride, or you hit the autoX course or whatever. And with these cars it's not unheard of for them to be different by a 1/4" on the bodywork, so then even the 10" section width would be super tight. But like I said, most cars can do it. Gotta measure.
Same point for the 275's. Depends on the tire manufacturer, car, etc. I've seen section widths on 275's range from 10.7" to 11.2", most are just under 11" which makes it a tight fit with the 1/2" offset hangers and shackles. I'm sure there are cars and tire combinations out there that would require a quarter lip trim to keep from rubbing. But you can't say you can't fit 275's on ANY Dart or Valiant even with a 1/2" offset, they will fit a lot of those cars. By the same token though, I wouldn't say they'd fit ALL Darts or Valiants either, too much variation in the bodywork and tire manufacturers to guarantee they'd fit every car.
And keep in mind too what the measured rim width is. The section width specs are measured on a certain rim. For example, 275/35/18's are usually measured on a 9.5" rim. I run mine on a 9" wide rim. So, the section width as mounted on my car will probably be a little less than the published spec. I mean, only a tenth or two, but that makes a difference.
