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Volvo wheels are spec'd by 3 numbers(besides the bolt pattern); width, diameter, and offset, i.e. 5-1/2JX14X20(on an old 240 steel rim), which you'll see near the lug bolt holes.
Width and diameter are pretty obvious, but offset is the distance(in millimeters, in Volvos) from the center of the width(which is in inches) to the inside bolting face, where the wheel butts against the hub. More positive offset moves the tire more towards the centerline of the car.
Front wheel drive cars tend to have more offset due to the placement of the CV joints; why 140s have so much is a mystery to me, but I know several people who have Volvo FWD wheels on 140s and like 'em a lot.
Having the center of the tire contact patch at the point where the steering axis hits the ground will make for the least turning effort; having the contact patch centered under the bearings makes for longer bearing life. There must be a jillion things an engineer has to look at to come up with the offset.
A good many years ago, I tried a set of what I believe were Coronas(a cast 240 wheel) on my '70 145, and they interfered with the front calipers, but I overcame it with a grinder(I can't remember where they hit). I did not like what they did for the handling, so I got a new set of 15" tires and drove away happy.
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