How much tire clearance is enough?

[4EyedTurd]

Test fitting 315/35/17’s on the old car to see what kind of wheel or rear end width I need. Lo and behold it fits with about 3/4” on each side. Mini tube would probably open up another 1 or so.

[BradM]

When they don't rub when you are driving, that's enough.

[dcs13]

3/4 is plenty. What you putting under the hood of that thing?

[46Tbird]

Different suspensions require different amounts of clearance.

An old suspension with sloppy bushings and mushy springs will need more clearance, than, say a brand new setup with rod ends and stiff coil overs.

I'm thinking that old Chevy tends toward the former, so I'd guess that 3/4" is not nearly enough. I'd suggest about double that to keep the tires off the wheel houses and fender openings while going up awkward driveways, etc.

[BLAKE]

When they don't rub when you are driving, that's enough.

While it's not a satisfying answer, I think this is the best answer. You've just got to try it out. Suspension is weird (especially on old cars) and doesn't play by any rules. Sometimes you'll have clearance on once side and not the other. Just have to drive it.

[NoClassic]

I would just fully compress the axle on one side and let is fully droop/extend on the other. If its does not rub doing this it likely never will on the street.

[4EyedTurd]

It kind of makes it a pain in the ass if I don’t have a rear end in it that’s even close to the right width. On the flip side the control arm bushings are shot and so are the springs so flexing the stock rear might be easy and give me an idea how far it’ll move. New rear springs and shocks are in the mail.

It’s just a stock 6.0/6speed for now, it runs but I’m fighting hydraulic clutch disengagement issues.

[cool cat]

is that a trailing arm suspension car? My Dad's 58 with worn out bushings had a lot of side to side movement, and even with stock tires they would get close to rubbing. New bushings are in and it should be good as it ever was. 59 and newer have some sort of track bar/panhard bar which should help locate the axle.