[mpg_numbers_guy]

What makes mpg testing difficult on the Prius is that the Prius targets a specific SOC (state of charge) for the high voltage battery. On the 2nd gen Prius, this is 62.5% (according to Dr. Prius), represented by 6/8 bars lit up on the gauges. If the battery SOC is > 63% the car will use more battery to get it back down to 62.5%, and if the battery SOC is < 62% the car will use more gas to charge the battery back up. So unless the starting and ending SOC of the battery is the same, or within 1-2%, any MPG findings are going to be skewed unless run over several tanks.....which is nearly impossible in a 2nd gen Prius due to the catastrophe that is the bladder gas tank....who ever thought that was a good idea to put in a car ever?

Tire pressure was probably the single best thing we did for the Prius, inflating the tires from 30 to 55 PSI made a world of difference. No noticeable difference in ride quality either, unlike my current Insight that is harsh as hell at 60 PSI.