No set-up is going to be exactly alike so I think your best bet would be to throw it on a dyno and go from there. Then you can actually see what tangible benifits you're getting for the changes you make. In general though, stock ECU fuel maps tend to be a little rich so you could reduce the fuel a little, however the VAFC doesn't have the capabilities to adjust the timing accordingly. With that said, throwing it on a dyno will be your best bet. If you want to do it yourself, find a friend w/ a wideband so you can see how it's effecting your A/F as well.