Finally: 100 mpg (US) round trip in the Blackfly - new and improved: 133 mpg

[MetroMPG]

(Originally written May 24/06)

I've been scratching this itch since I realized it was possible, and after supper today I pulled out the stops and headed out to do the city loop:



(101 mpg - click to zoom)

• ambient 70F - ish / 20 C
• 30 min block heater
• removed 55 lbs / 3% of vehicle weight (passenger seat, spare tire/jack, rear parcel shelf, misc.)
• used moderate load/low RPM acceleration technique
• alternator unbelted (I've been running that way since almost the beginning of this tank, except for approx. 30 miles of a 60 mile highway trip)
• made 3 of 6 traffic lights
• traffic was both light & accomodating (not as much of an issue with this acceleration technique)

Details: (click to zoom)



The tank MPG of course will change substantially between now and next fill-up (a highway trip coming up on Friday will pull it down to the mid/high 60's, I predict).

I've been recharging my battery with a combination of grid/solar. (I have a 15W panel that fits nicely on my cargo shelf, and gets 3-4 hours of good sun (when it shines) in my usual parking spot.

I was going to replace the starting battery with one of my deep cycle batts, but the one I have is too tall for the amount of space under the hood. I'm working on an alternative. It's not good for a starting battery to do a lot of discharge/recharge cycles to the depth I'm going without the alternator.

[MetroMPG]

August 27/06...

133 mpg (US)

Today I repeated the trip to the park to ride some trails (supposed to be crap weather tomorrow). Roads were pretty much deserted when I went just after supper - think I pulled onto the shoulder to let 3 or 4 cars by where the center line was solid, and signalled for maybe 6 or 8 to pass me where it was broken (and clear ahead). Managed not to hold anyone up. It was all very civil.

What's below are the results of mostly 2nd-3rd gear P&G, with some 1-2 as well. And a smaller amount of 3-4. The engine didn't quite reach normal operating temps on the first leg of the trip (8+ miles).

Interesting to see what the car is capable of. But the avg speed, as you can see is pretty low. ("RLS P&G: Really Low Speed P&G).

Then again... I just noticed that on my first 100 mpg r.t. its average speed was actually a tick lower than this effort. Interesting.

The "today" info is the entire round trip (just one trip today).

The "current" info is the return leg - slightly downhill, but barely. I think the FE is higher mostly because the car was somewhat warmed up. Though I also kept the speed a bit lower.

[MetroMPG]

6 or 8 months ago, I probably literally would not have believed this was technically possible.

For one thing, on this 133 RT I was virtually unmolested by other drivers - it was nearly all rural driving. Whereas the 100+ mpg RT's I'd been futzing around with earlier were all sub/urban driving with all the usual stuff: unpredictable lights, stop signs, pedestrians, and ... traffic (albeit small town traffic).

Another critical point: I touched the brakes once on the 133 mpg round trip, and that includes negotiating (ie. not "blasting through" approx. 14 turns at intersections, and 4 stop signs - which admittedly, I "rolled", but no more grievously than the typical driver.

[MetroMPG]

The mind set involved in doing this...

Ever seen/tried one of those motorcycle contests where the goal is to ride the course as slowly as possible without falling over? (Not trials riding, pylons in a parking lot.) Somehow it's sort of like that. More video-gamey than cardio-vasculary.

I suspect 133 isn't a "perfect" run. The car's absolute highest p&g FE is probably somewhere south of the blistering pace of 22 mph avg.