Wheel to Strut Clearance

[bucketfoot]

What is considered to be the minimum acceptable clearance between wheel and strut?

I've got a set of Apex 17x9 wheels from a fellow NASA RM member for my X1 that will primarily be for HPDE/tracking (he will take them back if there are any fit issues).

The only area of concern I see so far is with the front strut where I've got 4.5mm of clearance. The tires are 245/40s (about as small as you would want to go on a 9" rim), so I don't anticipate sidewall deflection being an issue. I'm kind of thinking anything over 3mm should be good.

Any comments/thoughts on this setup? Has anyone else gone with a wheel this wide?

[Westies]

I cannot comment on the 4.5mm being sufficient, however I ran 255/35 in the front without any clearance issues with the struts. My wheels are quite a low offset though.

[bucketfoot]

The car is pretty dirty since we had snow a couple of days last week, but here is the X1 with the new tires/wheels and a couple of shots of the clearance.

We have a couple of roundabouts close by that I was able to loop around at a nice speed and a big dip in the road that gives a good compression of the suspension. So far everything looks good.

The weather is supposed to be nice enough this week that I should be able to commute to work with them and give the fit a little more of a shakedown.