Ok, I have my new Magnum 500 wheels in my garage and I need to order my tires. The wheels are are 7" x 15". They have the 4 1/4" backspacing. I have stock suspension with front disc brakes. I also have chrome side pipes that hang down, so I want the tallest tires I can put on this 71 Comet GT so the pipes don't drag on speed bumps. I think that is all the info you need. Now, what is the best tire size? I have read a lot on this website, but nothing that seals the deal. I am not sure I want to put larger tires on the back, as I want to keep the stock look. I read where, perhaps, 205/70/15 will work? They are taller. But will they rub? I have also read where 225/60/15 work real well without rubbing, for sure? Then, if I want to put bigger tires on the back, I can install 245/60 there. Talk to me.....
Are you sure on that backspace measurement? It sounds a little deep, as in it would move the tire too far inboard. Our cars have issues with the tire being too close to the leaf spring, and that is where you might encounter a rub first. Backspace should be measured from the face where the wheel mounts to the axle to where the tire mounts inboard on the wheel. If laying a straightedge across the back of the wheel and measuring from there, it will inflate the measurement a bit. The width of that outer flange needs to be subtracted back out. 225/60/15 ought to work OK on all four corners with a wheel that if close to stock backspace. But if you need ground clearance, 225/70/15 is same width but taller. 245/60/15 fits on the rear most of the time, as long as the rims are close to stock, but some will start to be close to rubbing.Tire brands can vary as much as in inch in "the same size tire". My 265/50/15 Coopers are only 1/4" wider than a buddy's 245/60/15 BFGs. In theory that should be closer to an inch. Some brands run bigger than others. Size is based more on how that company meets the federal load rating for a given tire. Tall tire? ... a buddy had L70-15s (equiv. to a 245/70/15) on the back of his Comet back in the day. It looked ridiculous, but they did fit. That car had an absolutely stupid top speed too. It had the stock gear, and the tires were like overdrive. The safest thing to do, whenever stuffing a car full of tire is to physically take it to the tire shop along with your wheels, and have somebody with some experience thoroughly check the car out. Measure everything. These cars can be different from side-to-side. With front tires, clearance while turning needs attention too.
If it helps I run a 255/60/15 on the back with a 4.25 back space. I have .50 of clearance between the leaf spring and tire... I did have to trim some of the bump stop bracket off... On the front I run a 225/60/15 but I used a 3.75 back space on the wheel...
It looks like I have a choice between 225/60 and 225/70. I wonder whether the taller tire, 225/70, will rub on the front wheels? Who knows......
The 225/70 is 27-1/2 inches tall. That's pretty ridiculous for a Maverick (at least on the front). Those wheel arches are only so big. Not like a 2013 Dodge Challenger/Ford Mustang/Chevy Camaro wheel arch. I wouldn't go any taller than 25-1/2" on the front (but that's just me). Additionally, the higher a vehicle sits, the worse the handling will be. I think you would be happy with the 225/60.
It may seem counter-intuitive, but 225/60 on the front and 225/70 on the back can look good. Same width, but the back ones are taller. Street rod guys do this kind of thing often. The taller rear tire will take away some of that nice 3:40 gear that you just bought, though .... I would only do that if you just have to have the ground clearance.
Thanks for sharing all your thoughts and experiences. I don't want to look like a street racer. I want to stay stock, so I will go with the 225/60's and make it look old school with the Magnum 500's. Pictures are coming soon...
