Tested: MPG/fuel economy VS. speed, 2000 Honda Insight, 1.0L lean burn, 5-spd

[MetroMPG]

Finally got around to testing the U.F.O.'s speed vs. fuel consumption (at cruise, ideal conditions). This is all in top (5th) gear, with multiple mods in place (listed below) and with hybrid functions switched off (no electric assist/regen/charging during the runs).

For reference, the car's EPA fuel economy ratings are:

EPA city: 49 mpg (US)
EPA highway: 61 mpg (US)
EPA combined: 53 mpg (US)

Weather conditions:

Sept 7th, 2012
Sunny, 20 C
Wind S 5 km/h
Pressure 101.3 kpa
Humidity 71%

Raw numbers:


Speed ........ Set 1 .......... Set 1 ......... Set 2 ......... Set 2 ......... Avg .......... Avg

km/h . mph . W MPGUS . E MPGUS . W MPGUS . E MPGUS . MPG (US) . L/100 km

50 ... 31.1 ..... 129.4 ..... 132.3 ................................................ 130.9 ..... 1.8
60 ... 37.3 ..... 121.7 ..... 121.2 ................................................ 121.5 ..... 1.9
70 ... 43.5 ..... 113.5 ..... 117.7 ..........105.9 ......... 118.4 ........ 113.9 ..... 2.1
80 ... 49.7 ..... 94.2 ....... 101.9 ......... 94.9 ........... 101 ........... 98.0 ....... 2.4
90 ... 55.9 ..... 87.6 ....... 88.3 ........... 86.7 ........... 91.4 .......... 88.5 ....... 2.7
100 .. 62.1 .... 80.6 ....... 82.6 ........... 80.6 ........... 81.5 .......... 81.3 ....... 2.9
110 .. 68.4 .... 66.5 ....... 67.6 .................................................. 67.1 ....... 3.5


Methodology:

All readings were taken in top (5th) gear.

Air conditioning was off, windows were up (passenger side cracked an inch or 2).

Hybrid assist/charging was disabled during the runs.

Car was brought up to speed & leveled off before passing a "start" marker (road sign) where the computer was reset. Reading was taken after passing a "finish" marker.

Lean burn was fully engaged at all speeds except 110 km/h (partially engaged). If the car left lean burn due to throttle movement or an automatic NOX purge, the throttle was quickly adjusted (slightly lifted) to regain lean burn a.s.a.p., and speed was re-adjusted as needed .

Mods in place during test:

• disabled hybrid assist/regen/charge (via "Calpod" clutch switch mod)
• EPS off (electric power steering assist)
• DRLs off (daytime running lights)
• also, the following mods from: http://ecomodder.com/forum/showthrea...-km-18930.html ...
  
• partial grille block
• deleted passenger side mirror
• flat-folded driver's outside mirror (from a Suzuki Swift)
• deleted wiper arms: passenger side & hatchback

Route:

2 lane highway, straight, dry & level (follows river edge). The road runs SSW/NNE and can be found here: 1000 Islands Parkway - Google Maps . Test portion is 1.6 km / 1 mi in length.

Traffic conditions:

There was no traffic ahead in my lane; some traffic occasionally passed in the oncoming lane.

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See also: http://ecomodder.com/forum/showthrea...you-15182.html

[HyperMileQC]

You had no problem rolling at 50 km/h & 1083 RPM in 5th gear?

[MetroMPG]

It's OK in 5th on flat ground, sure. But it's the Understatement of the Year (TM) to say: not a lot of power in reserve!

[Jyden]

Thats amazing milage you get from that car. Very impressive. So it's acuatually more effecient as a pure gas car compared to hybrid?

[MetroMPG]

If there were identical versions of this car, the only difference being no hybrid components, I would say under limited, ideal conditions a very dedicated driver could probably beat the hybrid car.

A typical driver wouldn't come close to beating the hybrid though.

Most of my driving is with assist/regen disabled. But there are always times you're going to have to brake, and it's better to recapture some of that energy so you can spend it later - strategically - to save fuel.

EG: one drive I do regularly in the summer, I only capture energy for the majority of the trip - I don't use assist at all when the car might otherwise want to. The battery is then as full as possible when I get to a long, steep hill near the end, and that's when I "spend" the captured energy to minimize the fuel economy hit of climbing.

Regen is a wonderful thing.

[HyperMileQC]

Did you try P&G with the Insight? I have always wondered if it would be better in lean burn or constant P&G. I.E. 60-90-60 (km/h) P&G or 65 km/h Lean Burn DWL.

Also, would it be better to P&G with the 3rd or the 4th at those speed?

[MetroMPG]

I haven't tried it. One reason I love the Insight is I don't have to pulse & glide to get ridiculous fuel economy at ~80 km/h / 50 mph cruising speed.

If I had to guess though, I'd predict lean burn would still beat 60-90-60 P&G. Others have tried this, no doubt.

EDIT: I did lots of P&G during the 2012 SMCC Montreal fuel economy rally, but only because the course wasn't lean-burn friendly. (Lots of hills/turns/changing speeds, with tight time deadlines on each section.) It was enough to place well in the competition, but it was the worst "fill-up" I've had in the car since I got it.

[HyperMileQC]

So is it reallistic to say that with lean burn activated, at 65 km/h, you could see around 117 MPG / 2 LHK, or it is only in perfect test conditions?

[MetroMPG]

Ideal conditions. At that load, if you encountered any kind of hill, you probably couldn't hold lean burn.

Those numbers are on a level road, in warm weather.

[HyperMileQC]

I like to go between 65 & 80 km/h on the highway, so I could go at 65 when flat like the 401 , or go faster (80) in DWL conditions like my commute from Laval to St-Jérôme (autoroute 15).