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I drove my Insight from my house in Buffalo, NY to Hybridfest in Madison, WI, stopping at my sister's house in north-central Indiana on the way. I documented my mpg carefully on the best leg, the 457mi drive home from her house to mine.

Instead of taking the interstate from my sister's house to the Ohio Turnpike, I took the back roads. It was an interesting change of pace, and it cut that leg from 101mi to 85mi without taking any additional time. I got 88.8mpg for 85.9mi on that leg. :D

To me, that's FAR more impressive than the 98.2 mpg (plus some Wh/mi) I got in the FE competition in Madison under nearly unusable driving conditions, or even the 140-something mpg the winner got with his super-low-speed P&G with little regard for tailgaters and stop signs.

http://farm5.static.flickr.com/4120/4813880204_af2e59f738.jpg

Here's a picture of me having my cake and eating it too. That's 144mi of the Ohio Turnpike at 65-74mph (mostly 70mph) without dropping out of lean burn. Windows up on a fairly warm day.

The 72mpg, high-mph solution I ran in the hills of PA/NY dropped me below 80mpg for the day.

Other data from the long weekend:
Buffalo to northern IL with an overnight stop in Indiana: 9.725gal, 708.0mi, 72.8mpg
From there to Hybridfest and back to my sister's house in Indiana: 7.106gal, 493.9mi, 69.5mpg
Totals for the long weekend: ~30 hrs door to door, 1658.9mi, 22.65gal, 73.2mpg.

Now if only I could bring my drag coefficient down by ~20% (an enormous figure, I am aware), I should be able to lean burn under a much wider variety of conditions: while holding 74mph despite terrain, during gentle rain, up small hills, in traffic. Then I'd also have some headroom to modulate my speed with the throttle, instead of locking it at 31% TPS for HOURS. :p

Isn't the Insight 5MT a jewel of a vehicle? :D

I am so jealous. :p

Great Job Robert. You can't beat the mpg in an Insight 1

I agree with the OP that mpg's achieved during practical use of a car for commuting, errands, and travel are more significant than the amazing numbers gotten on defined loops at low speeds.

To me, the most impressive "practical-use" mpg in an Insight-I was when someone ("Billy?") drove his MT from the Pacific Northwest (Washington State?) to Hybridfest a few years ago and AVERAGED 104mpg for the several thousand mile eastbound trip. That's DAYS of >100mpg driving.

Others (Sean for one) and I have had shorter trips at mpg higher than that. Yesterday, for example, I had to run several errands in western CT in conditions that really work for me: temp in the low 90's, high humidity, almost no wind (tailwind would be better but tailwind both ways is unlikely). For the 116 mile loop the Insight-I gave me 112.3mpg. Mostly on I-95 at 45-55mph (psl is 55mph half the way, 65mph the other half, except for a 40mph construction zone - where I went 40mph). I'll try to put a photo of the FCD below.

The 30-40% "hit" in mpg you are taking could be reduced by:
- FAS-ing downhills rather than holding constant TPS - think of FAS as the ultimate lean burn
- slowing down - the Insight-I has great aero but still aero drag energy losses increase by the cube of the speed

Lightfoot, You would have loved Billy's announcement this year. He drove a little over 500 miles through Montana and averaged 92 MPG at 80 MPH!. He looked at aviation maps and found that a 25 to 35 mph would be on his route. He made great time and great mileage too.

I haven't done anything that far but I did drive from Coon Rapids, MN over to Elkhart, IN at 100.1mpg with a fully loaded car and some decent sized "hills" to climb on 94 through WI. That was a bit over 500mi IIRC.

To me, that's FAR more impressive than the 98.2 mpg (plus some Wh/mi) I got in the FE competition in Madison under nearly unusable driving conditions, or even the 140-something mpg the winner got with his super-low-speed P&G with little regard for tailgaters and stop signs.

I know in Austin whenever they have the Republic of Texas ROT bike rally, we all think "Gosh darn-it, there's going to be a bunch of loud, obnoxious bikers driving like idiots for the next week." I wonder if the Madisonians, or whatever they call themselves, think the same thing about hybridfest, minus the loud and obnoxious part.

So far, there hasn't been any confrontations with police. :) I'm sure some of the people on the route are annoyed. Madison has a very high ratio of hybrids. I think I noticed more Camry hybrids than standard.

Lightfoot, You would have loved Billy's announcement this year. He drove a little over 500 miles through Montana and averaged 92 MPG at 80 MPH!. He looked at aviation maps and found that a 25 to 35 mph would be on his route. He made great time and great mileage too.
I'd be much more impressed to see what he could have done under those conditions at a more reasonable speed, say 55 or 60mph. I bet with his finely-tuned right foot he would have been at 130-140mpg. Even I have averaged ca 115-1200mpg one-way on the 25 miles of I-90 eastbound from Worcester to Boston, but that has lots of long gently sloping downhills (with shorter uphills) - and those were under mild tailwind conditions.

I mean, after all, this is CleanMPG, not CleanMPG/H ;)

Leaving for Boston now, 90F forecast. This could be interesting, though NW winds aren't going to help much.

Isn't the Insight 5MT a jewel of a vehicle? :DAbsolutely, and this sort of highway cruising is exactly the sort of driving it was optimized for. Not that it's bad around town, but its lean burn and low drag really shine at higher speeds on level ground.

The hill strategy I want to get in on with MIMA is LB + assist on the way up, and LB + regen on the way down. I should be able to match my flat-land mpg with only a slight mph penalty. Or I could lock in on my mph target with assist, and drop into stoich to recharge the battery as needed.

Power to overcome drag increases with the cube of airspeed (hence winds are a HUGE factor), but drag force rises "only" with the square. Then there's rolling resistance, which is linear with speed.

Going 50mph instead of 75mph would drop HP required to a third (i.e. 5HP at steady state!) and thus cut in half the number of HP-hours per mile. If only the engine were sized and geared to be as efficient at 5HP/1700RPM as it is at 15HP/2500RPM, you'd see 150mpg on a good day. As it stands, the Insight is broken at those speeds. Whenever my impg goes well over 100mpg, I cringe, knowing that BSFC is poor and I ought to be FAS'ing or regen'ing. As a consequence of this and other factors, the best trip I've logged was around 101mpg.

I'm sure some of you would be getting 140mpg tanks if the Insight had a HSD-like hybrid setup so you could cycle the engine on and off ten minutes at a time.

I'd be much more impressed to see what he could have done under those conditions at a more reasonable speed, say 55 or 60mph. I bet with his finely-tuned right foot he would have been at 130-140mpg. Even I have averaged ca 115-1200mpg one-way on the 25 miles of I-90 eastbound from Worcester to Boston, but that has lots of long gently sloping downhills (with shorter uphills) - and those were under mild tailwind conditions.

I mean, after all, this is CleanMPG, not CleanMPG/H ;)

Leaving for Boston now, 90F forecast. This could be interesting, though NW winds aren't going to help much.
Apparently I answered my own question on today's Boston trip. After driving from my home in CT to Worcester MA, I started measuring a segment on the I-90 onramp in Worcester and took photos of the FCD at the Natick rest area and in downtown Boston. 136mpg for the 27+ miles to the rest area, down to 126mpg for the 44 miles to Boston. Conditions were 45-58mph, 90F, 5-10mph cross-tailwind (not the 25-35mph tailwinds that Billy had), about 450' drop from Worcester to Boston. Per Sean's recommendation, I shut off assist on uphills, FAS downhills, and drive everything else in LB, with regen if possible (restarts and EPS gradually runs down the battery otherwise).

It was strange because I normally try to keep the iMPG>100mpg, but when you're running an average at 120-130mpg, you really need to aim for 150mpg on the iMPG or you're dragging your average down.

Boston surface and expressway traffic killed my overall average for the complete trip (home-Boston-home), and I couldn't get it back on the return leg, probably because the NW wind was now a partial headwind.

Here are the FCD shots:

Way to go, John!!! :woot: :D:thumbs_up:

That's very impressive work regardless of speed and conditions: 136mpg from Worcester to Natick, and 112mpg from Natick to Boston. I'm very curious about the 136mpg leg: how much engine off time did you get in, and what was your typical mpg while the engine was loaded?

I've found it very hard to "pulse and LB". After a good long EOC, it can take up to a minute to get back into LB. Though I've gotten much better at coaxing it in to LB earlier. Also, this car LOVES the heat.

I'm very curious about the 136mpg leg: how much engine off time did you get in
I'm sorry I can't give an accurate answer because I was focusing on other things. Too bad there isn't a totalizer somewhere for that.

But I usually FAS any downgrade longer than roughly 0.2 miles and steep enough to maintain speed or at least not lose speed to my minimum acceptable MPH too quickly. BTW, at 50mph more downhills are "coastable" because they don't need to be as steep to maintain this speed.

If the battery is not topped off (thanks Sean!!) I may leave the ICE on and the car in gear on a downgrade and get regen. On steep downgrades by using fuel cut, or on less steep downgrades by driving with the MIMA joystick eased back (juggling joystick and gas to keep the iMPG and MPH to acceptable levels).

On a known route like this one I can FAS towards the end of an uphill and bleed off speed down to my 45mph "floor" approaching the crest before a downhill and then let speed build back up on the downslope.

One thing to keep in mind: I had been driving for >1hr before I started the segment. So the car was fully warmed up, no warmup "hit" to the mpg.

what was your typical mpg while the engine was loaded?
I tried to hold it to 150mpg whenever I could. At that level the ICE is very lightly loaded so it's difficult to maintain. Just stopping at the rest area and getting back up to speed again dropped the average about 5mpg, and I recovered only part of that.

On uphills I just accepted whatever mpg I got and gave priority to maintaining speed >45mph (minimum mph is not posted on I-90 and it's 3 lanes, but still....). I just hoped that the more efficient burning of fuel at higher loads on the uphills and the potential energy gained in the climb would offset the higher consumption.

I've found it very hard to "pulse and LB". After a good long EOC, it can take up to a minute to get back into LB.
I haven't had much luck with pulse and LB either. Driving the uphills and coasting the downhills is what I do instead. On dead flats I just try to cruise along in LB. Fortunately this area is mostly rolling terrain, ranging from gently rolling to moderate hills.

Mine drops right back into LB after a pulse though, haven't noticed that problem.

Mine drops right back into LB after a pulse though, haven't noticed that problem.

I have to coax mine just a tad but that consists of extremely light load for about 2s -- I just keep the instantaneous way up and let the car lose a little speed, then ease into it as the A/F ratio gets leaner.

I meant "LB and Glide", obviously. Well, if easing it in works, I may have to play with the technique some time.