Wheels Fitment

I know this has been discussed and I've read all econoline wheel size related threads. But... while I was changing my shocks and looking at the worn out tires on my rig I thought, spend $ on new tires which she desperately needs, or throw that money towards getting some sweet rims And I've kind of set my mind on some cragar style rims, ar etc in 17" size.

I found a link to a calculator that has been extremely useful in helping me figure out what wheel/tire combos will fit:

www dot rimsntires dot com/specs.jsp forum won't let me post hyperlink yet

It may help some others out in the future.

The van currently has 195/75/14's on stock-style 14"x6" steelies with what I'm pretty sure is a 4" backspace.

That yeilds a wheel that is 7.7" wide x 25.5" tall overall with offsets of 3.35" frontside and 4.35" backside. These wheels fit with room to spare and don't fill out the wells much, esp in the width dept.

So after some, hopefully, careful measurement and calculation I've come up with what I think I'm going to go with.

Fronts- 17"x8"/+.5" offset and 225/45 rubber which yeilds a wheel that is .6" wider both sides than the current wheel in position and .5" smaller in diameter. Looks to be no problem lock to lock turning.

Rears- 17"x9"/+.5 offset and 255/40 rubber which yeilds a wheel that is 1.15" wider on both sides and also .5" smaller in diameter. Looks to be an easy fit as well.

Here's the thing, I'm also considering going with 225/50's up front and 255/45's in the back which would give me +.4" front and +.6" diameter back over current wheels which I think will be fine. But I'm thinking about lowering the van some and not sure which ones to choose.

What do you guy's think?

Sounds like you've done your homework and have a good grasp on the variables!
I thank you for laying it all out and sharing!

Since the tolerances on older cars was a lot looser than current stuff, and the commercial vehicles (vans/trucks) were even more 'sloppy', each van is different. Add in 40 years of use and finally you want to lower it too, and there is no one that can determine if it will all work better than you!
You can go a bit conservative and run a slightly narrower wheel/tire combo that you know will fit. Or you can push the limits, buy the biggest/widest set you dare and then make any mods needed to make them fit and clear.

If you have a bunch of big friends, you can have them climb into each corner to check clearances and ride heights or get a bunch of bags of sand/cement to do the same.