What do you guys think is the safe minimum space required between caliper and rim?

 

As long as it isn't physically rubbing, anything. The rim and the caliper have a set distance unless something goes wrong.

I did some googling and 1-3mm has worked for people.

 

Sorry, I forgot about my friend google on this one. Thanks.

 

Haha. No worries. I know I have like multiple inches. But it seems people have gotten away with 1.5mm or so. It's still your choice. What did your gap end up being?

 

I have less than 1mm clearance to my ITR calipers, dollar bill barely squeezes thru

 

Are you talking about the barrel of the wheel or the spokes? The spokes deflect slightly with cornering force so I would leave more space for those than the barrel.

I'm running 11" Wilwoods under stock Miata wheels with about 2mm clearance to the wheel weights on the barrel right now (tire shop guy didn't listen to me and put them in the wrong area). No signs of rubbing after 150 autocross runs and 5-6 hours of track time.

 

I am talking about the spokes not the barrel. The rims are mugen MR5 and 11" Wilwood also.