MAX Update No. 68: Idle Speculation

http://www.motherearthnews.com/green-transportation/100-mpg-idle-speculation.aspx

MU68HoneybearIdleThe honey bear is back. 

One advantage of hybrids over ICE cars (that's Internal Combustion Engine, if you're new here) is they don't have to idle while waiting for the light to change. That's no small advantage with normal cars. For example, according to my ScanGauge II (about which I'll write more some day), my '96 six cylinder minivan burns 0.43 gallons per hour at idle (with an occasional bump to 0.44), or in other words, about a gallon every 2 hours and 19 minutes.

Unfortunately, I can't plug my ScanGauge into MAX, because MAX doesn't have an OBD II port. That's the little on-board diagnostic (hence OBD) socket under your steering wheel, if you have a mid-'90s or newer car. The OBD protocol is a way to get electronic information from your car's fuel injection computer to the mechanic who is wondering why it's running funny, information that includes how much fuel the engine is burning. The ScanGauge II translates that info into plain English, and puts it where you can read it, on the screen of a little box that sits on top your dash.

MAX's fuel injection is strictly mechanical. There's no computer, thus no data to read. So I plugged in the HBFCI (Honey Bear Fuel Consumption Indicator), calibrated to 4 fluid ounces (118 milliliters really, 'cause it's hard to find anything that will measure a fluid ounce precisely), and goofy as it may look, that space between the honey bear's neck (marked with yellow zip-ties) and knees (marked with blue tape) is within a percent or two of 4 oz.

So what did I learn? After I got MAX warmed up, I filled the HB to just below the lips* and let the engine idle. When the fuel level got down to the neckline I started the timer. When the fuel level got down to the kneeline, I took this photo.

Four ounces in 13 minutes and 12 seconds. That's 3.425 minutes per ounce. Times 128 (fluid ounces per gallon) is 438.4 minutes per gallon, about 7 hours and 18 minutes. 

Okay, both my “about”s are a tad imprecise, and it's probably better to round the results for comparison purposes, so I'll say about 2:20 (2-1/3 hours) per gallon for the minivan and 7:20 (7-1/3 hours) per gallon for MAX. My conclusion is, MAX won't get better fuel economy by making MAX a hybrid, because the weight we'd add (batteries, motor, etc.) would do more harm than the hybridizing would do good. For a heavier vehicle, now that's a different story, but here, we're talking about MAX. 

*No honey bears were harmed in the making of this MAX Update.   


Photo by Jack McCornack

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