I have 71 Dart with front disc breaks. Is the back spacing 4.00 or 4.25??
Also, I am having my rims widened. Should I go 6" or 7" wide?

Your original wheels have less than 4" backspacing as they are only 4.5" wide. The 15x7" wheels used on police cars are 4.25" backspacing or .25" positive offset (ET6mm). On a car with the '73+ disc brakes (breaks is an action which destroys) 15x7" with 4.25" backspacing works great. You may be able to use slightly less backspacing with Kelsey Hayes brakes, but the biggest I went with the '72 Duster was 14x7" slotted mags with a 215/60R14 tire.

How much does it cost to have the wheels widened any more?

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Joshua

If you run 6 or 7 inch wide rims in the front, you MUST get backspacing of at least 4 inches and you will be runnign very skinny tires to clear the frame.

For example, my brother has a 74 Duster that is running 68 Dart front fenders. The wheel opening on the 68 fenders is a bit smaller than your 72 fenders, but pretty close.

The Duster currently has 15x7 rims with about 4 inches of backspacing. The biggest tire that fit on the rims and that clear the fender and the frame are 205-50-15. With the later and larger wheel opening you could probably get away with 215 or even 225 width and 60 to 70 ratio sidewalls, but that isn't much bigger.

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Casually looking for a Clifford hyperpak intake for cheap.

I resenting bought a 14" rally wheel with a 4.00 back spacing and the wheel would not clear the factory disc break caliper. Does that mean I need a 4.50 beach spacing? Collin's in Bellflower widens wheel for $60 each painted.

With the limited information being given I'm thinking the wheel that wouldn't fit over the brake caliper was not a Chrysler-made wheel. I believe there are Magnum 500 wheels that fit drum brake cars only.

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Joshua

Hi, the wheel I tried to fit was the 1971 dodge Rally wheel 14 x 6 with 4.00 back spacing.

With factory Rally wheels and factory disc brakes you should have zero issues.

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Joshua

I put 205/60-15s on Magnum 500s onto a 73 Dart Custom that had disk brakes. The Magnums had 4¼" back spacing. No problem with clearance front or rear.
I have 235/60-15 on cop car wheels on a 72 Demon with BBP disk brakes. Wheels have same BS as Magnums. No problem with rear clearance. Front wheels are extremely close on outside. Fenders hung a little wide to ease situation. Admittedly, the front end is set to the low side of factory tolerance. Things might be easier if I went to a more middling setting.
If I had to do it over again, I'd probably would go with no more than a 225/60-15 tire on a 7" wide wheel with 4¼" back space.

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