backspacing for race wheels

["Brad Cox" <coxb@trimofran.org>]

I'm about to purchase a set of 13x9 inch wheels for autocross.  Does anyone
run a similar setup on a 6th gen civic?  If so, what amount of backspacing
did you require in order for adequate clearance?  BTW, I'll be on Hoosier
Street TD 225/45/13's.  Also, were there any problems getting the 13" rim to
clear the front disc brakes?  I put together a jig to help me determine my
backspacing, but I'm not sure I trust my results, and the wheel manufacturer
doesn't have the data.

Thanx you!

-brad