The big thing is the AMA safety code specifies the set-back rules based on engine displacement. You should follow that (or, if your field can handle it) go with even larger set backs.
NJ, Huh? That's not far from here at all, depending on where in NJ you are. If you guys want to come down to an RCCA contest, we have 4 scheduled here in MD.
Also, if you do schedule an event and want folks from out of your club to attend, let me know. I run a small website (with event calendar) and email list at
www.MidAtlanticCombat.com that is dedicated to promoting combat in the area. If you hold an RCCA rules event that doesn't conflict with events on the calendar, I'll almost certainly make it up there.