18" wheels
I usually have to replace the rear tires 3 times before I have to replace the fronts. So I save money by not replacing all (4) tires every other time. So I need to have wider rear tires.
Can I ask why is everyone so afraid to mini tub and relocate the springs on their A-bodies?
First on your logic, if you were rotating the tires the rears would last longer and you'd go longer between replacements. The amount of wear doesn't change, it just gets evenly distributed. You're spending the same amount of money, you're just not doing it all at once.
As far as the mini-tub goes, I don't think people are "afraid" to do it. But it does require a pretty significant amount of welding, which not everyone can do themselves. And, it's not a small amount of work so it's not cheap to pay someone to do it. Guys that are paying to have it done (or are doing it as a business) are paying(or charging) $1k to $1,500 just in labor. See this thread
cost to inboard rear springs.
Then there's the old "why do you need tires that big"? With Dart's and Valiant's you can get a 275 in there with a 1/2" offset and a little trimming on the quarter lip. Would it be nice to get a 295? Of course. But do you need a 335? Not unless you're putting down 900 hp. And remember, Duster, Demon's and Dart Sports can get a 295 in the back with the 1/2" offset and some trimming. So, I think it becomes a diminishing returns thing. 275's will support a pretty high horsepower car, and are more than wide enough to make an impression at an autoX. Yeah, if the space was there I'm sure more people would go a little bigger, but I also don't think most people want to run 335's. And a relocation and mini-tub is a lot of work if you only want to add another 3/4" of section width you probably don't
need to begin with.
And of course, there are plenty of folks that don't want to do that amount of cutting on an original car.