I packed the nikko cars away already, but I still have the white turbo aero buggy, and some other aero buggies. I believe they all take 8 AA batteries. The Nikko shockwave boat is the only one that takes a 7.2V RC pack. Speaking of boats, I also have the 27mhz electronics for a 9.6V tyco boat as well.....it could be from a typhoon though, I'm not sure.
If you give me the name of the nikko cars you're interested in, I'll look through the boxes this weekend and let you know if I have any of them.