Thanks. So much for neutral coasting........

 

Actually, I have verified that even at highway speeds you can press on the gas pedal just enough to cancel regeneration but maintain high MPG... not actually infinite (ICE off) but around 80 or so. Of course you decelerate since this is basically a coast but there's barely any gas going into the engine.

 

I've found that I can maintain 50 MPH at 80 MPG, and 60 MPH at about 60 MPG. I couldn't do this when I first got the car, but I've gotten better with practice. When I started, I couldn't hold a steady reading on the instant FCD anywhere between 50-100 MPG (seemed like it was either dropping fast or rising to 100 in a coast). Now I can pretty much put it where I want to and hold it there. Now I really understand why you guys call the I-FCD a game gauge

 

i tried getting into the ev mode between 20-35 mph and found it was quite easy on a flat/downloped terrain. the engine revs would drop to 1100, FE pegged at 100, and 0-4 bars of assist showing.

is it possible to enter into this mode at say, 60 mph or higher?

 

Sure, it works the same way at any speed. The electric motor won't be strong enough to keep your speed constant, but it will extend your coasting distance. It even works going uphill if you have a soft enough touch on the throttle.

 

Hi NASAngineer:
___I am hearing some very good things here as this is the one place where the lean-burn capable HCH-I’s had a large advantage over the Prius II. It sounds like Honda kept a very high mpg mode at lower speed cruise but without lean burn somehow? Are you positive you can maintain 80 mpg at ~ 50 mph and that you are not using any EV or assist when doing so? Maybe a 3 or 4 mile DWL segment at 45 - 50 mph with no drop off of SoC would verify this? This is really that important! If so, you have the ability for a HS FAS with nothing other then a gentle pull back and reapplication of the accelerator from what you have done with us earlier, a FAS all the way down doing the same without all the gyrations we go through now, a steady 80 + at 50 mph, and all we need to hear about is a SoC management technique through a HS and LS P&G and low speed traffic jam EV mode use.

___By early next week, hopefully you can give all HCH-II owners a detailed summation of how to transition into the non-regenerative EV/Glide mode under a variety of sceneries, maintain a slower speed w/ 4 bars or less of assist in a very low speed traffic jam with appropriate buffers, bringing her all the way down w/out regen, and how to maintain a slow speed cruise at 80 mpg on the instantaneous.

___I know I have been asking quite a bit of your time and effort as of late (pushing would be the more appropriate term ) but you are the only HCH-II owning member we have with the mindset to not only ride the edge of the envelope but push it as well. Besides the fact that you reside in a climate that is still conducive to extreme hypermiling to figure this all out and who can reply with enough detail in laymen’s terms for other new owners to digest, learn from, practice, and use day in and day out in the future. Anyway, I want to thank you again for both current and future HCH-II owners as well as myself who are interested in what an HCH-II is really worth when pushed and how to achieve it through a variety of real world roadway obstacles and scenerios.

___Good Luck

___Wayne R. Gerdes

 

I was not specifically testing for this, so that's just from my memory. Indeed I need to go out and do some controlled tests for this.

I also went out yesterday with my wife (she being armed with notepad and stopwatch) and did some acceleration tests. I'm very curious to determine what is the best way to get up to speed, from 0 to 20, 30, 40+. Should I use assist and also use more gas because the ICE is revving higher, or accelerate gentler w/o assist? With assist, the I-FCD reads lower, but it takes less time to get to speed. Without, I can accelerate with a higher reading on the I-FCD, but it takes longer. Where's the sweet spot?

All tests were done accelerating from 0-35 MPH. I did 5 tests for each scenario, here are the averages:

50% Assist: 4-5 blocks on the I-FCD (~20 MPG), took 15 secs.
No Assist: 6-7 blocks on the I-FCD (~30MPG), took 30 secs.

The data seem to support the idea of using 50% assist (the MPG hit is small compared to the time gained). However, these results also include the skill of the driver. I think with more practice, I could probably improve the I-FCD numbers. Another thing I noticed is that the I-FCD numbers are not directly tied to throttle position (as I mentioned before). The I-FCD seems to always read 1-2 blocks below 10-15 MPH (in fact I think the gauge doesn't work at all below 10 MPH, since it always drops to 0-1 when coasting to a stop below 10). As my speed increases above 10-15, the I-FCD goes up, and I can gradually increase my foot pressure while maintaining the I-FCD reading (or even increasing it, the higher the speed, the better MPG I can get while accelerating). More practice is needed here.

Thanks for your great comments and encouragement!

 

Ok, I did some more tests for sustained mileage at various speeds. Here's what I found:

- To sustain 40 MPH, I held the I-FCD at ~70 MPG
- To sustain 50 MPH, I held the I-FCD at ~60 MPG
- To sustain 60 MPH, I held the I-FCD at ~50 MPG

These tests were done over a 4-5 mile distance. SoC remained at about 88% the entire time.

It appears that what I was seeing before (50 MPG @ 80 MPG and 60 MPG @ 60 MPG) was not actually sustained. At longer distances, it becomes apparent that speed is slowly bleeding off (about 1 MPH every 10 secs. @ 50 MPH/80 MPG).

 

Thanks for all that information NASAgineer... I don't know how you get your wife to help you in the process, mine refuses to tag along. Thanks to her too!
Jason.

 

Well, we've only been married a month, so maybe that's part of it

How do these numbers compare to what people see with the pre-6 HCH's? I'm curious whether the skill of the driver or the car itself is the bigger factor.