1971 Demon 17" Help

225/60-15 on 15x7/4.25”

Tire Diameter:
25.60 in.
Section Width:
8.98 in.
Tread Width:
7.20 in.
Minimum Recommended Wheel Width:
6.00 in.
Maximum Recommended Wheel Width:
8.00 in.


255/45-17 is only 3/8" taller, Section width is 1" wider. And you can run it deeper in the wheel well.

My rears are 255/60-15 on 15x8/4.5bs. If running an 8.75 rear I could get a 275/60-15.

1.03” t-bars. New OE suspension and just have 650 miles on the restoration so I am just going to creep up on the alignment. I’ll get corrected geometry UCA’s and other parts to compliment the Borgeson.
If you are committed to running a 15" wheel I think the 225/60 is about the best you can do. Maybe a custom bs like a 15X7.5 with 4 3/8" bs with a 245/60-15 but it's an inch taller and wider than the 225. The one inch gaps would be 1/2" and you may not be able to lower it with t-bars any further. You would defiantly need to be running the SPC arms going that route.
With a 400 treadwear 15" tire being the best you can get then hunting for more than a 225 seems futile.

I don't know if that helps @michiganpat but if you want to run a 17" that would be a good tire.


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I used the Typ. Perf. Street on the Skosh.
This car will live the rest of its life in this trim so this isn’t “The One”. I looked at a 1969 Barracuda today and it was too expensive but I also started seeing where a Valiant, Duster, Demon, and Dart Sport are what you want to build for maximum tire and suspension. I kinda don’t even want a A-body Barracuda after looking at it from that aspect. Now I’m looking for a Duster or Demon that will be this one’s twin race car!
gorgeous car. I need to get under my car and start taking measurements this weekend. I'm going to be doing a front suspension rebuild and drum to disk conversion on the front over the winter using A body disc spindles, for the rear I'm probably going with an XJ rear or YJ/TJ rear since those are what are easily available around me. I know on pre-73 cars the wheel mounting face gets pushed out further with discs, is it the same way going from the '73-up front drums to the stock disks? I thought the change to the drums in '73 pushed them out closer to the disc setup. my car currently has 205/70R14's on stock SBP rallyes and that's about the biggest diameter tire that will fit w/o catching the front corner of the fender with the stock rallye's bolt spacing. if I go 17's, my initial thoughts were a 235/45R17 in front, and 255/50R17 in back, likely Nitto NT555's....