DIY, 100 MPG Car is Back on the Road After 20 Year Hiatus

by Benjamin Jones on October 13, 2008

Through the forums I learned about the interesting story of a two men who built a super-efficient car back in 1984 to combat high gas prices, only to pull it off the road again when prices became more manageable. The two, Craig Henderson and Bill Green, founded Avion in 1984 and then spent two years building a 100 MPG sports car, which they managed to eke 104 MPG out of in a South-North trip across the US in 1986.

After making the trip for less than $15 of diesel fuel, the two hoped to find a company interested in the design, but as the Bellingham Herald notes, that wasn’t the case:

Not only was the Avion painted in “arrest me for speeding red,” as Henderson likes to describe the color, but the lightweight car’s fuel efficiency couldn’t be beat.

He was wrong about the interest.

“Nobody really cared. Big deal. Fuel was cheap. There was a glut of fuel,” Henderson, 51, recalled earlier this week. “Fast forward to today. Things change, don’t they?”

This time around, the fuel crisis doesn’t look like it will have the same kind of wait-and-see solution it did in the past. No one thinks prices are going to drop again, and even bigger fears like global warming and dwindling petroleum supplies make the need for a long-lasting change even more salient.

That’s why Avion has jumped back into the game to compete for the Automotive X Prize and $10 million. Given that the goal of the competition is to break 100 MPG in a production-ready vehicle, I would say Avion is well on its way to taking top honors, though the competition is sure to be fierce.

As for the car itself, it’s designed as a sports car, combining sleek, fast looks with aerodynamics to turn heads both on the highway and at the pumps. It’s built around a Mercedes diesel engine, but a lot has changed in engines, especially diesels, since 1984, so I’m sure there are some changes to be made there. Best of all, it could be mass-produced for about $20,000.

Check out the Avion website for more on the car, and our own aerodynamics forum for some more DIY aeromods. I’d drive one, how about you?

Popularity: 10% [?]


1 capnrob October 13, 2008 at 12:39 pm

Sleek. If it was “sleak”, it would involve pylons, dinosaurs, and time loops.

2 John Roberts October 13, 2008 at 3:09 pm

Wow, that is one wicked looking ride!

3 raddet October 13, 2008 at 4:53 pm

So, what’s the crashtest rating like? 0-stars?

4 daniel October 13, 2008 at 5:06 pm
5 October 13, 2008 at 5:12 pm

Why are we so reliant on the combustion engine? It’s one of the slowest evolving technologies, and we’re near the end of it as a means. Hybrids are a band aid solution. At least electric cars are a step in the right direction. Admirable feat mentioned, but isn’t it time to look at a new means of propulsion?

6 dan October 13, 2008 at 5:21 pm

Disel is not a sports car.

7 John October 13, 2008 at 6:11 pm

No, the 40 MPG version had a Chrysler/Shelby 2.2L Turbo GASOLINE engine in it. The Mercedes diesel version broke 100 MPG. I bet they can do even better with today’s improved diesel technology.

…and please don’t tell Audi that “Disel is not a sports car.” They’ve been racing a diesel-powered Le Mans race car for a couple of years now with GREAT success.

8 mgroves October 13, 2008 at 6:26 pm

“No one thinks prices are going to drop again”

Is that so? What about the story I read today title, “Two-week gas price drop is biggest ever”?

9 sillygolem October 13, 2008 at 6:46 pm

@daniel: This version has a turbo 4-cylinder gas engine instead of the diesel.

Still impressive considering that was a formidable motor at the time. This motor got about 25mpg highway in the tiny Dodge Omni GLHS.

10 Mobius October 13, 2008 at 7:20 pm

“Built a 100MPG sprts car”. Sorry – WRONG.

Nothing that gets 100 MPG (especially a Diesel!) can be called a sports car.

What they created was something that looked like a 1960s sports car, with an amount of power that wouldn’t pull the skin off a rice pudding.

Look, props to these guys for making a streamlined diesel vehicle go 100 mpg back in the day, but they would have had to work like the devil to get that mileage (it’s not worth it, working that hard) but we have to face facts:

1) You can buy diesel powered cars that are properly safe, properly warranteed and properly appointed that will already get 75mph – just not in the USA!

2) Their ride will dangerous as all get out: it’s probably made from toothpicks and firbeglass to keep the weight down. We know those cars kill people.

3) Slippery like that – no way you can bring a car to market like that. Marketing want to add holes and scoops and stuff like that.

4) You can’t have wheels like that sorry. The brakes will rapidly overheat with no air flowing through them – and you die when the brakes catastrophically stop working.

So, over all, a decent effort – just a completely impractical one. Leave the fuel efficient motors and lightweight cars to the brits and the Euros – they know what they’re doing.

11 John October 13, 2008 at 7:26 pm

No one designs sleek futuristic cars like this anymore. Why not? Why does everything nowadays have to be butt ugly?

12 will October 13, 2008 at 7:34 pm

@ daniel

From the same website:
In our testing the car we were able to achieve 80 mpg At 70 mph and an astonishing 114 mpg at 55 mph

13 Martin October 13, 2008 at 11:05 pm

Seriously, I don’t get you Americans on that magic 100MPG number … The VW Lupo I used to drive (until some beginner crashed it) made 100 MPG in 1999, VW is about to release a car that actually does 160 MPG in 2010… (

14 Martin October 13, 2008 at 11:06 pm

Small correction: The 1-Liter-Auto is bound to achieve 238 MPG…

15 Meg October 20, 2008 at 1:28 pm

What a cool car! I would love to see one of those in my driveway!


16 Tony Rusi October 24, 2008 at 2:38 pm

The Avion gets 113 mpg in real world driving. If VW comes out with a 160 mpg that is only sold in Europe two years from now, well good luck with that. The big deal is that anyone anywhere can make 200 gallons of biodiesel with a home algae bioreactor for about a dollar a gallon. It is all about supply and demand. I think this is why OPEC is dying. An electric version would be even better. XP Vehicles is making an inflatable electric car. I predict that we will see one dollar gasoline for a very long time now! What a difference two weeks makes!

17 Car Dude October 28, 2008 at 5:48 pm

Though I still find it hard to believe that this car can do 100MPG, I still think that the Avion looks cool.

18 Craig Henderson October 31, 2008 at 12:47 pm

The Avion did not average 100MPG It averaged 113.1 MPG! and I have over 30,000 miles on it and the car is over 25 years old.

19 Steve January 12, 2009 at 3:22 pm

Anyone who thinks a diesel can not be a sports car is simply not thinking…
Hasn’t anyone seen a diesel F250 or F350 easilly outrun a fast sports car, for example, a corvette, lambourghini, ferrari.
It is easilly done.
My brother has a diesel F250 that outruns a corvette by about 2.3 seconds.

Next time you say that a diesel can not be a sporty vehicle. DO SOME RESEARCH.

20 God July 6, 2010 at 12:30 pm

Hi Mobius,

There is a bit of a disconnect between USA and Europe with regard to what a sportscar is. USA thinks a sportscar is something that goes fast in a straight line, with power uber alles and a dismaying lack of interest in handling. While those crazy Europeans like to be able to turn as well as go fast.

A popular 15 year old Lotus Elise does 0-60mph in 5.8s, with just 118hp, while getting 50mpg with a clunky old 1.8 l engine and a drag coefficient CdA of 0.59m² and a rolling resistance of .01 it needs about 9kW (13hp) to keep the car moving at 60mph.

Nowadays that engine could be replaced by a 1.3l turbo diesel with more power (>90hp/l is common). And that diesel can have a BSFC of 200 g/kWh so 9kW needs 1.8kg =2.4l of fuel for 100km, which is exactly 99mpg at 60mph.

In reality the extra urban drive cycle speed is slower than that and so uses less fuel owing to less drag, but transmission friction sucks a bit of power too, so 100mpg would not be totally unrealistic for a turbodiesel Elise.

Using an 120hp 800cc turbo DI gasoline miller cycle would probably give 80-90mpg too.

A little bit of work on the car shape and this sportscar could well be over 100mpg.

21 jamesskaar February 28, 2011 at 6:40 am

to gravity control… better, gasoline and diesel engines became popular for cars because of electric starters, the two competing technologies were steam and electric.
electric was dropped, few companies kept work on them, they slowly improved, when the oil crises hit it came back, and are now in a usable state, but far from super.
steam, was improved for cars many years after they lost the popularity war, they got to the point electrics are now, usable and safe, development continued with crackpots, but the technology could easily be revived and put gasoline cars to shame.

Comments on this entry are closed.

{ 3 trackbacks }