I'm a new poster trying to master all the hypermiling skills in my old car before my 08 prius comes in. He mentions roller coasting in his interview when he trekked from Chicago to NY. My question is what exactly is roller coasting? Is it take a slow acceleration up hills, then speed down them while trying to enter warp stealth? If anyone knows please chime in. Thanks much Brandon
It is another label of what is called 'terrain driving.' The principles are: ascend the hill at an engine efficient speed - for example the speed of a truck in a climbing lane is perfect, ~55-60 mph ballistic glide on the downgrade - let the speed increase to whatever is safe avoid climbing a hill so fast as to put the engine in inefficient power ranges, 65+ depending upon grade If you are on a four lane road, this works great if you stay in the outside lane and perfect if there is a climbing lane. But on a two lane road, the passing zones are often after the crest of the hill and accelerating here while creeping up the climbing side will madden the following traffic. However, I would recommend heading over to CleanMPG to get Wayne Gertes' exact description of "roller coaster." But before you do, you might take a peek at the PriusChat stickies that address hybrid driving as well as Wiki. Bob Wilson
You'll want to get a scan gauge so you can monitor what the engine is doing for settings you can control. When climbing a hill you want to pick an RPM that will barely maintain or slowly lose speed as you're climbing. On the back side of the hill, either use warp stealth of super highway mode depending on hill size/state of charge/ terrain after the hill. I don't think anyone has published a chart on when to choose one over the other. After you get a scan gauge I'd suggest watching how the car works in cruise control, what RPM/IGN/TPS does as the car moves along then practice and learn how to do it on your own.
Consider using "warp neutral" to get a feel for how it the car should de-accelerate if your doing warp stealth right.
