1971 Demon 17" Help
Yup, for sure!
Craig's fenders have the corners completely cut back because of rust, which I think not only effects the location of the corners but also how much rigidity there is in the rest of the fender lip. And he pushed the fenders out with turnbuckles as well.
Thing is, although he has the QA1 LCA's he has the later version with the bump stop that eliminates the additional suspension travel gained from the older style without the bump stops. If you look at his pictures when he had his car sitting on the bump stops, and think about that wheel being an inch higher, you can see how much it would decrease the clearance.
I think the same goes for the "price buster duster". He's running stock LCA's, so, even if he's running with shortened bump stops there's less suspension travel there.
Ultimately I think they both show that you can get a lot of tire under there if you're willing to roll/push/modify the bodywork. If you wanted to put an import style fender flare on there you could probably run 335's if you wanted to. But they also show how much ride height and suspension travel change the clearance you need.
to keep things simple, what works on a 14 or 15" wheel as far as offset will work the same on a 17. if you're running stock chrylser 15x7's with 4.25" backspace (1/4"+ offset), then the same size rim with a tire the same overall width and height should work (i.e. if there is a 215/60R15 on the front now on that 15x7 with 4.25" offset, that is 8.5" wide and 25.2" tall, then a 215/50R17 (8.5" wide, 25.5" tall) should fit on a 17x7 with 4.25" offset....on the front, you'll likely need to keep the outer face of the wheel/tire in the same spot to not have fender clearance issues, so if you want to go to an 8" rim, you'd likely need to go from the standard +1/4" offset to +30-32mm (basically all of the extra rim width is pushed to the inside), which is approx. 5.75" backspace. rear is really going to depend on your axle. met a guy with a '73 dart sport and a stock 8.25" rear. to get the tires centered in the wheelwell, he needed custom 15x7's with 3" backspace (so that would be the same as -1" offset)....for me, these wheels kind of speak to me....
Vision Wheel 148-7865SGMF19 Vision American Muscle 148 Shift Satin Gray Machined Wheels | Summit Racing
Lol. Uh, yeah, if you want to run 17's with the same height and width tire as a 14" or 15" wheel/tire then you can use the same backspace, that should be REALLY obvious.
What is not obvious is that you
can't use a 5.75" backspace on a 17x8 in the front or the back on an A-body. In the front with a 17x8" you can go up to about 5.6" of backspace with most rims, because the outer tie rod will interfere with the rim after that. So, no 5.75" backspace on the majority of 17" rims up front. But you can still run a 255/45/17 on the front with a 17x8 and a 5.6" backspace, which is much wider than anything you can pull off with a 15" rim. And of course in the back, regardless of which factory rear axle you have, you can't run 5.75" of backspace as it will put you into the springs.
There's also no reason you have to run a 15x7" with a 3" backspace, even with an 8.25" rear (which are narrower than the 8 3/4's). A 15x7 with a 4.25" backspace works just fine with most tires that will fit back there, 4" might be better with a 255. A 3" backspace would actually be limiting the width of the tire you could run. He likely just wanted his tires out closer to the quarters to look like they filled the wheel wells, because that 3" backspace doesn't actually center the wheel in the tub, it puts it closer to the quarters. My '74 originally had a 7.25" rear axle in it, same exact width as an 8.25". I was able to fit a 17x9 with 4.75" of backspace and a set of 275/40/17's on it in the back when it still had the factory spring locations and quarter lips. To be truly centered I think it would have needed to be about 4.5" of backspace, but that's still only a -12 offset, not the -25 those 3" backspace 15x7's had.