Review: Ultra gauge vs MPGuino

[Niner]

When I first decided to hypermile, I decided on the MPGuino - it was half the cost of the Scangauge (for the prebuilt one; home built could be even less). It did everything I needed, installed easily, and had a good sized screen for a large single-number display.

However, after deciding I wanted to do some mods - particularly grill blocks - I decided I needed a temperature gauge. An aftermarket analog gauge was $30, but for twice that I could get an Ultra gauge with everything in one. So I went that way.

This last week I've been running them in parallel as I get the Ultra gauge calibrated, so I thought I'd share my thoughts.

Ultra Gauge:
+ screen is slightly bigger, and it can contain more numbers comfortably
+ very slim, and small. could easily be mounted over the rear view mirror
- "instantaneous" MPG value is actually averaged over as much as 3 seconds. When I use my injector kill switch it shows MPG in the hundreds, then the 200's, then finally switches to 0 (rather than infinity or 999)
- the screen looked bigger in the pictures (I was picturing the 3" screen they use in GPSs), so the "big" numbers are still smaller than the "big" numbers on the MPGuino


MPGuino:
+ open source, open design
+ easier to make it look "built in"
+ works on non-ODBII vehicles
+ instant means instant - very easy to see minute changes in your pedal or grade on MPG numbers
- possibly due to the default screen, there are lines in the big numbers. this makes it harder to glance at
- limited to data you can generate from VSS and injector signals

All in all, I find both to be good products. In general, I'd prefer the MPGuino for the open source nature, but needed the extra inputs (I believe there is an ODBDuino project - I don't know if that gets everything). I had thought about putting the MPGuino in my non-ODBII truck, but my wife is interested in having it, and she puts 10x the miles on her car as I do on the truck, so that's its new home.

[RobertSmalls]

That woman is a keeper.

I'm planning to run a SG and an MPGuino side by side, and here's another key difference:

The MPGuino measures fuel consumption, while the SG and UG just estimate it based on MAP/MAF and RPM readings. The SG is off by a few % if you P&G, and it's useless for reading the mpg of a lean burn engine. MPGuino should be dead on.