caliper/rotor clearance

[dannyho]

I'm doing a custom/budget brake setup and the rotors I may use are not of the typical dimension ie .875 in, 1", 1.25 inch. If i were to use a typical 4 piston caliper what would be considered too much clearance?
Could I have a pad spacer made up? but if we're talking .07" on each side, might the piston be able to deal with it? I think I just measured my rotors somewheres around 1.09". In a perfect world I'd be using wilwood's calipers for 1.12" rotors, but in case it doesnt work out that way any help would go a long way
thanks
Dan

[Apogee]

Most calipers are designed to work on a range of rotor thicknesses based on the depth of the piston bores, seal dimensions, pad thicknesses and body dimensions. The easiest way to figure out if the caliper is compatible with a certain rotor is to contact the caliper manufacturer and ask them. The next alternative would be to pull the pistons, measure the seal depth/position, and decide for yourself.

A good example of of this is running C5 calipers on C4 HD 13" rotors...the C5 rotors are 32mm thick whereas the C4 rotor is 28mm thick, a difference of 4mm or .160" overall, approximately what you're looking at.