So the way to get really killer FE in the HCH on a rural highway is pulse and glide between 25 and 42 or so, with FAS on the glide phase, right?

Then, if one is forced to travel at interstate speeds, what is the best way to obtain xcel or Hot_Georgia-like FE? My current strategy is to try to keep my instantaneous FE gauge above 60, and drive with load up and down hills (with N coasting down bigger hills). This usually results in speeds around 55-60. However, the highest FE I've gotten for a long interstate trip using these techniques is around 60. Any interstate-specific tips from the experts would be appreciated.

 

MPG is calculated as MPH / GPH. Miles-per-hour divided by gallons-per-hour. Your GPH (fuel consumption) is reduced a bit by driving 25 mph compared to 55 mph but your speed is more than halved and you end up getting much worse MPG. Think of it like someone using half as much gas per hour but turning a 1-hour commute into a 3-hour commute. Obviously the total gas used is more.

Nearly all cars are their most fuel-efficient at 55-60 mph. You will suffer if you go below 50 mph.

 

I don't think so. The "sweet spot" for maximum fuel economy is going to vary, but a general rule of thumb is the speed (or just past that speed) your car is in it's highest gear. I don't know if 45mph is my 5-speed Insight's "sweet spot", but it's definitely under 55mph.

While you could get opinions, perhaps the best thing is to cruise on an uncongested road and try different speeds.

 

I have, and I cannot get over 50 mpg at 40 mph or below with my '06 unless I coast to a stop so the engine can turn off. It happens consistently only between 50 and 65 mph.

 

The important thing to note is that "sweet spot" of greatest fuel economy varies from vehicle to vehicle. In the instance of the 2006 HCH, it's apparently above 50mph. This is the exception.

 

I've gotten a sustained 65 MPG @ 48 MPH with no assist in my 06. It's hard to tell if this is a true steady state condition though since it only lasted about 20 seconds before I hit an uphill segment.

 

Hi Civicduty:

___Boy there are a lot of threads to immerse ourselves in this evening!

___Since you own a ULEV based HCH-I, you have that magical mode called Lean burn! I know how it acts in Tbaleno’s CVT and I know how it acted in the Insight. Just push her up to a slow highway cruise, back off the throttle just a touch and very slowly re-accelerate back up to your target. You should see her camp in the 80 mpg range. I am not talking about 65 mph w/ A/C but maybe 50 - 55 mph with little wind, maybe some traffic side draft to keep your momentum up, and DWL as if it were your last gallon of gas. High pressures in the tires and some Mobil1 0W-20 between the marks to round out your setup and you will be hypermiling with the best of them in no time! Add a slow mover for a close in draft and I have the feeling she could sustain 80 mpg + at 65 mph but its going to be a hairy long distance drive let alone finding a slow mover for any kind of lengthy distance Grab as much leanburn at slow speed cruise using the DWL technique as you can, as much drafting as you can, FAS’ when you are coming up to a slow down and you should see a mid to high 70's average - sustained in 70 + degree temps. If you are going to stop or slowing to < 30 mph to avoid obstacles of some kind, I highly suggest a full blown FAS vs. an idling Glide. Your HCH’s CVT has a buttery smooth reengagement below 35 mph in my short time behind Tom’s windscreen. Use it or lose it as they saying goes …

___CGameProgrammer, you just need more experience is all. The Insight’s sweet spot is around 32 mph at just above idle in 5th while DWL. You can almost cruise at a pegged 150 mpg instantaneous there. More like 125 mpg’s but it bounces around into the pegged range every once in a while Tom’s 03 CVT based HCH-I really reaches it peak around 52 mph and you can back off with the CVT locked into her highest gear ratio down to ~ 45 mph before she falls back off again in my experience. The HCH owners will have a much better idea as to their HCH’s capabilities then I as I do not have the time behind the wheel that I would like to speak with authority on them. I have a suspicion that your HCH-II acts very similar although without lean burn, you are going to get what you get? That is unknown just yet but NASAgineer will know once he sets his HCH-II up for some out of this world FE after another 3 or 4,000 miles The AH and std. Accord reach their best at ~ 42 - 45 mpg once OD locks up while in a slow speed cruise with congested traffic while DWL. Because they have more power then sense, they can pull into and hold drafts at their maximum FE respectively that the Insight would never be able to. I am not sure about the HCH-I or II but I sure would like to try them out again Tom’s HCH again and the HCH-II for the first time …

___Good Luck

___Wayne R. Gerdes

 

Actually I find different sweet spots in my HCH I. There are times at 40 mph I get 80 mpg on the instantFCD and other times on the freeway I find myself getting 75-80 mpg at 70 mph and this can be for as long as several miles too, I think temp. and a tail wind or am following a truck has lots to do with it. I have to say that I usually don't go 70 mph but there are times that I have to as I try and stay at 56 - 60 mph on the freeway.Kevin