Went about making a jig from a 16" long piece of angle and a 12" piece of 1/4" allthread... dilled some lugbolt holes at one end to mount, and rotated the wheel (axle on jackstands) to determine the largest circumference without hitting... bounced the car at the tight spots just to check interferance under leaf spring compression.
Drilled hole at outter end of angle for the allthread to check width interference based on backspacing of 4" American Racing 8"x16" wheels.
I can do a total diameter of 29" and a maximum section width of 9", without skirts of course. This should make 235/65R16's an easy fit. I'm bettin 245's would fit as well, if slightly re-route the exhaust pipe closer to the frame. An inch deeper offset would be about all any 245's would take before hitting the inner-rear fender well.
So, I'm off to buy/mount one side to confirm my findings.
I have a pair of those Aerostar coils for the front, but chickend out installing them when I saw how short they were (uncompressed) compared to the uncompressed stock units... like almost three inches. I knew it was to lower the front, by about 1" - 1-1/2", and the spring rate is suppose to be stiffer, but the visual contrast was more than I had for experimenting at that time. Next time I tear down the front, or get bored with the billizon other projects going on, I may put them in just to see.
Cheers... Brian
Cylinder Index = 84
Current Experiment = `57 Tbird, Grand Rapids, Michigan