I have no idea what the difference may be other than the pistons if you are using the same heads. I used what the guys from Hughes engines came up with (I got the entire engine package parts from them to avoid mix and match) and it also was aligned withe the compression results from the summit racing calculator tool. At the end of the day that was their compression suggestion based on what I told them I needed the engine for. Very happy with the results so far and the parts quality from Hughes.
