[PrematureApex]

I know what you mean, we ran Motecs (and much older systems) in our FSAE cars a decade or two ago.

Yup, with just the JB4, you can achieve good results with either setup.

A backend flash alters the stock ECU tune (either expands factory ranges of operation, and/or shifts control of certain parameters to the JB4 for more control). The JB4 itself is a piggy running over top of the factory tune. So a backend flash, like a traditional tune, is altering the factory tune, in one aspect of another.

More specifically, for the N55, the backend flash changes the base fuel and timing map to better match you'd want for larger turbos, so the JB4 has less work to do altering on the fuel and timing end.

Not sure where stand alone flash tunes with the N55 are.

You can read a bit here...(edit, that's for the N54...let me find it for the N55 big turbo swaps)

http://www.n54tech.com/forums/showthread.php?t=20563

But literally a google search for N55 backend flash, BMS, etc. will provide a lot of info. There's a few years of solid tuning/background out there...which is very good new.