[MetroMPG]

A non-scientific comparison of this weekend's results against another trip, pre-tail:

This weekend's round trip results with the tail in place:

• Trip length: 177 mi / 284 km round trip, 1 person, approx 10% city, 90% rural roads (50 mph / 80 km/h limit),
• Average speed: 39.5 mph / 64 km/h, 60 mph max (posted limit on the majority of the drive: 50 mph / 80 km/h). Note: that includes time stopped, and reflects going through 1 small city, several small towns, hamlets.
• Driving style: cruise control on the open road (with some engine-on coasting down steep enough hills), engine-off approaching stops/turns, where practical.
• Conditions, there: light rain, just above freezing, negligible winds. Return: dry roads, just above freezing, gusty (up to 40 km/h) crosswinds.
• Results: 52.4 mpg (US) round trip = 4.5 L/100 km (54.3 there, 50.4 back)

A previous round trip, pre-tail, but with the 15 mods in place:

• Trip length: 168 mi / 270 km round trip, 3 people, approx. 10% city, 45% freeway (100 km/h / 62 mph posted limit), 45% rural roads (80 km/h / 50 mph limit)
• Average speed: 40 mph / 64 km/h (per ScanGauge, includes time spent sitting still). Includes going through 1 small city, 1 town, 1 medium city.
• Driving style: mostly with cruise control on the open road (close to the speed limits -- a little over, a little under, depending on traffic).
  Engine off coasting, where practical (approaching stops/turns).
• Conditions: windy (gusts to ~40 km/h), temperature -2 to +2C, roads dry or damp.
• Results: 44.3 MPG US = 5.3 L/100 km = 53 MPG Imp.

But note these trips don't make for an ideal comparison -- it's unlikely this thing is worth an 8 mpg improvement in identical conditions. Even though the trip length, average speeds & ambient temps were close, they were on different routes, with different loads. The pre-tail trip carried more people & probably had a higher "rolling average" speed.

I'm just comparing them out of curiosity until I get some better controlled numbers. (A speed vs. mpg set that can be compared to pre-tail speed vs mpg).

The "as-good-as-possible" testing (A-B-A) will come sometime later.