For the first few thousand miles on my HH, I was having a hard time getting a good technique for when traffic was light on the highway on my commute to/from work. My mpg is great when the traffic is heavy, but dips a lot when there's no traffic and I can go the speed limit (65-70).
From my driveway to the hiway, I have about 2.25 miles of neighborhood streets with less flat and more gentle grades/hills. Next, I have about ten miles of hiway, half flat, half gentle grades with a few hills (one long hill going up to work, but a great coast coming home). Then, off the hiway again for about another 2 miles on access road/side streets to the office. I have two interchanges, and in San Antonio, that mean going through two asinine traffic lights.
I can get into the dead band coast, pretty easily now, but it was tough and required lots of practice. I personally don't notice any difference between coasting with my foot off of the pedal vs. a dead band coast. I cannot perceive any resistance when the indicator shows battery regen, or a reduction in resistance when I stop regen and hit the dead band. Maybe the HH is too heavy to make this noticeable. I haven't found a good road yet (or maybe I really haven't looked hard enough) that is flat to test the difference with some good data, to see if the coast will be longer in the dead band with the same speed.
I have discovered a technique that seems to help with highway speeds. I know many have noticed the effectiveness of using cruise control, but my experience on my gently rolling highways in San Antonio has only resulted in a best mpg of about 25-27 using CC. I have found I can do better than the CC by using the instantaneous mpg meter as a feedback mechanism. Use the dash meter, viewed with your peripheral vision so your eyes don't leave the road too much. This technique seems to require a minimum speed of about 45 mph
. Wayne is not going to like it because it uses the battery/elec motor, but my hiway elevations and traffic conditions just don't permit effective p&g because the coasts bleed down to fast because of repeated uphill grades.
Here's what I do on the hiway when the traffic is moving smoothly at the speed limit:
Get up to speed as you normally would on the hiway, let's say 60 mph
. Instead of p&g, which in this situation will really annoy other drivers in smoothly moving traffic, I ease off the gas pedal very slowly until I see the mpg meter hit somewhere between 40 and 60, then I freeze the pedal. In this condition, the eCVT seems to find a taller gear, and the elec motor kicks in to assist. Holding this, the elec motor will come on and off, I guess depending on whatever, I don't know. This state bleeds off speed much more slowly than a p&g, even with gentle uphill grades. I can hit this state at 65 or 70 mph
, and I can keep this state for several miles until my speed bleeds down to about 55. At this point, I very slowly depress the pedal until the mpg meter hits at or just below 20. In this state, i'm using the ICE, but the HH accelerates very gradually without tanking my avg mpg. Once I'm back up to 65 mph
, repeat. Using this technique, I've been able to keep my mpg above 30 so far for my current tank (I'm down to about 1/4 tank having travelled about 370 miles at 31.0 mpg avg). If I can keep this up, this will be my first 30+ tank, on the computer anyway. We'll see what my manual calc says when I fill up.