re: mpguino, The main variables (which you can set through a menu) are:
microseconds per gallon
vss pulses per mile
injdelay
To calibrate with a pump, you do need to be very consistent, some details here:
Mpguino calibration - EcoModder , though there are certainly other ways to calibrate, this is the general purpose method, and used to good effect by many folks.
re: pulse width, each injector pulse is measured in the realm of microseconds, and will have a constant (injdelay) subtracted to account for injector opening time.
So the modified pulse widths and the vss pulse counts are accumulated and displayed as instant, tank, and current "trips". Current being useful for short term experiments also (resets after car/engine stop for 7 minutes/whatever you set it to).
System voltage can affect accuracy as the injectors open more quickly or slowly, so some recalibrating is in order if you remove your alternator, i.e.. Don't know that fuel pump voltage matters as much as the regulator pressure setting though, sure "It Depends").
Quite a few honda users here, don't know about turbo though, but even if you only get a relative reading it is useful for ABA testing, or just plain "beating your high score".
PGFPro, Does your del sol maintain a reasonably constant pressure differential between the fuel rail and the manifold?