Tein EDFC
 

DPE, do the EDFC motors mounted on top of the front dampers fit under the stock front tower brace? In general, is there anything on the 8 that needs to be permanently removed (or replaced) in order for those motors to fit in the confined space atop any of the front/rear dampers? ... looking at the Tein Flex and EDFC for my 8 in the near future ...

I apologize; I've overlooked this for a month almost! Anyway, I'm sure you've found your answer elsewhere but to my knowledge you don't have to remove/modify anything to install the EDFC motors. Now, to install them you have to run wires to the four corners of the car, which may involve drilling through the firewall and things of that nature, but as far as where the motors go there appears to be adequate room to me. I have not installed a set on an RX-8, so I can't say for sure. I'm sure someone will jump in and correct me if that's inaccurate.