Hey Scott, I do at least 3-4 full tanks and average it out, and then reset ecu for the new fuel and repeat.
Both my V36 and R34 does better with BP98 as well over the Caltex and VPower...
P100, pulls better and does similar K's to BP98 or just a bit more.
Actually thinking about it, P100 pulls better over Caltex and VPower....comparing to BP maybe same or so...that one I am not too sure considering I use either one.
Recently though I got my V36 tuned with P100 in it...
Do you think mixing BP98 and P100 would be a problem?