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Pretty basic question, but I haven't needed to do this in the 50 odd years I've been messing around with cars. My '66 '500 currently (318 Poly, 8 3/4 rear end) has 14" "Road Wheels" on it & they look great. However, what I REALLY want is a set of 15" Magnum 500's, just like the ones that were on my '68 GTX. Priced them out at Summit & we're planning a road trip to Ohio in the Spring to pick up a set. I'm a bit confused about the proper way to measure the dimension from the rear of the bolt surface to the rim (back space?), also the diameter of the bolt circle. Placing a straight edge across the rim at the outside surface of the tire bead, I come up with about 3 3/4". Measuring across the bolt holes, mid point to mid point and skipping one hole, I come up with 4 1/4". Am I doing it correctly? These numbers seem "close" to what I've read but not exactly the same.
Help!
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It will be 4 1/2 , outside to center of same holes you measured.
Back spacing is from edge of wheel to bolt surface
The Idaho Andy
I love the smell of race fuel in the morning
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X2 on the 4.5" bolt pattern
how to measure back spacing-
http://www.summitracing.com/expertadvice...ackspacing
Clean as a whistle
Smelling like a rose
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The Magnum wheel can fit Furd and Mopar.... so the center bore is also critical. Here is a great simple diagram with everything you need.
![[Image: wheel_offset_diagram.gif]](http://www.sizeitup.com/images/wheel_offset_diagram.gif)
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Just what I needed, boys. You guys are the best!
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I can tell you from experience ,money wise,what the biggest tire will fit in the rear,why does it cost so much money when you screw up?
66 Coronet 500 convertible 440,727,2500 stall,was 430 hp, we ain't got a clue now, just get in and enjoy the rumble
