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Some of you may remember that TS contributor, 1985Gripen, was recently involved in a car accident. Thankfully he was OK with just some whiplash to contend with, but the accident left his work-supplied vehicle a write-off.

His replacement vehicle is a Chevy Impala LS, and it’s E85 capable. As an E85 supplier has recently opened in LA, Gripen - ever the environmentalist - couldn’t resist giving the biojuice a try.

The results were very interesting, and given that BioPower could well be better tuned by the time it hits US shores next year, it’ll be interesting to see what others get on the BioPower system when it arrives.

Here’s his writeup on the experience:


According to the U.S. Environmental Protection Agency ( this car supposedly gets 16 mpg on E85 combined and 22 mpg on gasoline combined (28% better). However the test the EPA runs is really flawed when compared to the “real world”. They don’t take hills into consideration, for example.

I ran my car in every imaginable situation, from hills to high-speed highway driving, to stop-and-go freeway traffic, to idling for an hour in traffic at the border. Sometimes I had the air conditioner on. This was probably a perfect example of “mixed” driving.

When I first filled the tank with E85 there was still 3.246 gallons of E10 gasohol in the tank. The tank’s capacity is 17 gallons. I tried to get as close to empty as I could, but it’s hard to judge how to have enough gas in the car so you’re not stranded on the side of the road but still get as empty as you can.

Considering it’s winter here I’m guessing the E85 was closer to E70, meaning my tank of E85 was really about 20% E10 and 80% E70. I’m no mathematician, so what’s that come out to? Like E75?

Anyway, on that mix and some SERIOUSLY “mixed” driving I got 19.7 mpg.

I came pretty close to running out of gasohol the next time I filled- up, with only 0.587 gallons left in the tank. But I was able to calculate the fuel economy running on gasohol (E10): 20.2 mpg.

So surprisingly running on E75 (or whatever) didn’t have nearly the 30% mileage “hit” than is predicted. In fact, I only got around 3% worse fuel economy running on E85 than on regular unleaded.

Perhaps some of this is due to the fact that California’s regular unleaded gasoline already contains up to 10% ethanol by volume, I had about 20% E10 in the tank when I filled-up with E85 (or E70), the E85 probably contained double the gasoline percentage due to the “winter blend” (30% instead of 15%), and slightly differing driving conditions (I didn’t drive the exact same course).

I still would have expected my fuel economy on E85 to be at least 20% worse than gasohol under these conditions. Saab’s BioPower fuel economy difference between E85 and unleaded gasoline is supposed to be even less due to the optimization of the ECU.

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