15x8 & 15x6 (74 Dodge Dart)

235-60 15s are perfect on a 15x7 stock mopar rim (4.25" BS). We've run that on a dart, no issues at all. The Dart sport has a bigger wheelwell. I know guys running 255-60-15s wtih no clearance issues.

For 235s to rub on the outside, on a Demon, the offset of your 15x8s must be pretty small. I'd guess ~3.5" or so.

Do you recall the spec.?