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Discussion Starter #1
Hello, I have a loop around my house where I often do some mpg tests. The loop is 4mi long, flat at first and then up a steep hill, and back. It typically has a red light followed by around 2000 feet at 35mph, and repeat. I make sure I start and finish with the same numbers of battery bars. 75°F, no a/c.

My first loop was me trying my very best at fuel economy with very slow accelerations and Eco mode. It returned 71.8mpg.

For a second loop I decided to floor it after each red light or stop (not going after the hard point on the pedal though). Basically, I try to reach the posted speed limit as fast as possible and then either cruise or slowly lose speed. Still in Eco mode. To by biggest surprise, it yielded 70.5mpg.

Note that the engine was already pretty warm at the first loop. It's a relatively small loop so the error might be a few mpgs, maybe 5, but even with that, I find it a very good surprise that the mpg is in the same ballpark. Meaning you can "have fun" for a very small toll on mpg. I also remember one of you saying that his girlfriend drives more aggressively and returns better mpg so that makes me think it's possible.

I don't think this "technique" works when red lights are close to one another though. I think you need some cruising distance to rip the benefits of a hard acceleration.

Thoughts?
 

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Yeah, you can do this in short burst without hurting fuel economy much. I do this sometimes at traffic lights to have some fun. Keep in mind this only works when the battery is at optimal temperature/battery level while it's warm outside.
 

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My first loop was me trying my very best at fuel economy with very slow accelerations and Eco mode. It returned 71.8mpg.
[...]
For a second loop I decided to floor it after each red light or stop (not going after the hard point on the pedal though). Basically, I try to reach the posted speed limit as fast as possible and then either cruise or slowly lose speed. Still in Eco mode. To by biggest surprise, it yielded 70.5mpg.
I think the 'mpg magic' result was close for both cases because the speed was kept <45 mph, and the car is primarily driven by the electric motor(s) in Honda's hybrid design for <45 mph speeds.

The Insight's max torque occurs at 3000 RPM and involves the electric motor (directly or via combined hybrid mode), instead of the gas engine alone. Since gas engine use is minimized, mpg results are maximized:
  • GAS ENGINE ONLY = 99 lb-ft torque @5000 RPM
  • ELECTRIC MOTOR = 197 lb-ft torque @0-3000 RPM
  • COMBINED HYBRID = 197 lb-ft torque @0-3000 RPM
From the Alex on Autos video for Honda hybrid design, "below 40-45 mph, only the electric traction motor drives the vehicle forward (with power from battery pack or from generator tied to engine). Only above 40-45 mph can the clutch between the two motor generators can close, to send power mechanically without involving either electric motor."
 

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Discussion Starter #5
I think the 'mpg magic' result was close for both cases because the speed was kept <45 mph, and the car is primarily driven by the electric motor(s) in Honda's hybrid design for <45 mph speeds.

The Insight's max torque occurs at 3000 RPM and involves the electric motor (directly or via combined hybrid mode), instead of the gas engine alone. Since gas engine use is minimized, mpg results are maximized:
  • GAS ENGINE ONLY = 99 lb-ft torque @5000 RPM
  • ELECTRIC MOTOR = 197 lb-ft torque @0-3000 RPM
  • COMBINED HYBRID = 197 lb-ft torque @0-3000 RPM
From the Alex on Autos video for Honda hybrid design, "below 40-45 mph, only the electric traction motor drives the vehicle forward (with power from battery pack or from generator tied to engine). Only above 40-45 mph can the clutch between the two motor generators can close, to send power mechanically without involving either electric motor."
Interesting video! At speed under 45 mph, the electricity still comes from the gas engine. The way I see it, if you floor it, you are getting close to the gas engine 5000 RPM peak torque and that's why it's still pretty efficient. The electric motor has a flat torque plateau at speed under 45mph so it can be taken out of the equation.
 
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