The 100 Mile-Per-Gallon Alternative Car

100 mpg with off-the-shelf technology? Jack McCornack isn’t crazy, he just believes cars can have a lot better fuel economy than we’ve settled for historically. Enter MAX — the MOTHER EARTH NEWS entry in the Auto X Prize competition, a $10 million race for 100 mile-per-gallon alternative cars. This article details MAX’s origins and the early stages of its development.

| August/September 2008

Learn about the 100 mile-per-gallon alternative car contest. Meet Jack McCornack, the brains behind MAX — the 100-mpg hopeful that you’ll be able to build.

Learn about the 100 mile-per-gallon alternative car contest. Meet Jack McCornack, the brains behind MAX — the 100-mpg hopeful that you’ll be able to build.

Photo by Jacky Leggitt

Without any whiz-bang technology, we’re building a 100 mile-per-gallon alternative car for the Auto X Prize competition. MAX may not win the Auto X Prize, but it will prove a point that 100 mpg is within reach without futuristic technology.

The 100 Mile-Per-Gallon Alternative Car

There’s a contest underway to build 100-mile-per-gallon (mpg) cars that are practical and feasible for mass-production. Known as the Progressive Insurance Automotive X Prize, it will award $10 million to whomever can crack the 100-mpg puzzle and best demonstrate the achievement during cross-country races. When the races start in 2009, I’ll be behind the wheel of a sporty two-seater that will be as cool as it will be fuel-efficient.

Through a series of MOTHER EARTH NEWS articles and updates online, and at Kinetic Vehicles you can come along for the ride.

Who are You, and How did You Get This Awesome Gig?

I’m Jack McCornack, and I have a history of tinkering with “alternative” vehicles. I was an energy conserve-and-economize zealot before Jimmy Carter wore a cardigan. In the early ’70s, when we were only allowed to buy gas every other day, I drove past the long gas lines in a homemade contraption that got 125 mpg. In the late ’70s, while working with MOTHER EARTH NEWS, I made aircraft that got 40 mpg on home-brewed alcohol, and I helped with the tilting, three-wheeled 3VG concept vehicle. (You can read the original articles about these projects in The Flight of the Microlights and a two-part series Hey, Take a Look at Our Three-Wheeled Car and A Hybrid Vehicle Leaning Toward the Future: The 3VG (PART II).) These days, my latest company, Kinetic Vehicles, supplies parts (and sage advice) for lightweight do-it-yourself sports cars.

After a more than 30-year snooze, our country is waking up to the fact that treehuggers of yore were right — we’re running out of easy oil, if not all oil. So now the time is right for me to tinker anew and throw my hat into the Auto X Prize ring. The timing couldn’t be better: I’ve been building another cheapskate vehicle that just might fill the bill.

$10 million!! What is this X Prize thing?

The X Prize Foundation has an intriguing system of sparking technological breakthroughs: “revolution through competition.” The basic idea is to set lofty goals and give big money to the individuals or companies who best meet those goals. The contests are named after the people or companies who put up the prize money, which is how Progressive Insurance got in on the act for this X Prize. (For more on the Auto X Prize, see Racing to a Revolution.)

4/23/2014 5:15:14 PM

Hello, I have been looking for HHO kit. I found one of the kits below, but not sure it is worthwhile to purchase. Can you please recommend good HHO kit, which you tried? My target is 20% MPG increase with reasonable ROI. Thank you in advance!

john teague_2
2/13/2009 10:36:48 AM

how much does or will it coast now?

tim flinn
2/11/2009 9:34:11 AM

The Locust (low cost) was based on the Lotus 7 (now the Caterham) that, depending on engine used, can hit 150mph)and can out accelerate every Italian super car. The orginal Lotus 7 was a kit car. The Locust like the Lotus orginated in Britain in the last ice age. The French sell the Maxem (Maxham?) which is based upon motor cycle parts, uses the Kubota diesel and does 90mpg (or so a proud owner claimed to me) but top speed is not sixty. It is a weather proof four seater (for 4 tiny Frenchfolk). It is road legal in Europe, but I wouldn't want to crash into anything larger than an empty matchbox. Look it up on the web.

clinton crawley
10/18/2008 11:25:14 PM

Gary Brown in Georgia has been putting tractor engines in trucks and cars. He's getting about 50 mpg in trucks and about 60 in some cars. His website is I personally feel that HHO gas(hydrogen or Brown's gas)made from plain or salt water is the only way to go. Three fourths of the earth's surface is water--you can't find anything more abundant that that.

jack mccornack
8/11/2008 3:05:25 PM

:-) It takes more power to generate hydrogen than is released by burning hydrogen, but many people tell me it works for them. I've yet to hear a convincing explanation of how it's supposed to work, but there are lots of discussion groups on the internet and you may learn something I haven't.

geetz romo
8/11/2008 12:49:42 PM

tack on a hydrogen (HHO) booster and see how much better mileage and lower emissions you get. You should get better torque as well.

john rockhold
8/7/2008 3:33:26 PM

(forwarded from Jack McCornack) When Colin Chapman designed the Lotus Seven, he called it a "four wheeled motorcycle," and from a passenger safety standpoint, that's pretty close. Is it "street legal"? Could an auto company do this? Sure it could--Caterham Cars got the rights from Lotus years ago and you can buy a brand new Caterham Seven today. But we can and should do better. You're seeing MAX at the beginning of its development, and the Auto X Prize rules demand we get our car to current safety standards before the driving competition begins. We're working on side intrusion, and we're already pretty good on front and rear intrusion (and sadly, I can prove it--see my blog for details). Ditto for emissions, we already meet the latest standards for agricultural equipment and we think with a year's work we can meet auto standards too. So stay tuned, and feel free to prod us if it looks like we're not making fast enough progress.

john rockhold
8/7/2008 1:19:50 PM

(forwarded from Jack McCornack) Hi George, tell us more! I know that chassis-wise (and currently body-wise), this car's inspiration dates back half a century, however, it has other features to bring it up to current needs. I think folks should have been building these in 1981 but once the first wave of the fuel crisis ended, interest in fuel efficiency kinda dried up. Anyway, it would be good to be reminded who was keeping the faith back then, and I sure don't claim to be the first to think small-car-small-engine is a good way to go.

robert petrach jr.
8/7/2008 5:54:50 AM

This article is a tremendous disservice to the readers. This is a death trap. The frame is touching the occupant, no crush zone, no room for intrusion. The engine would not come close to passing emissions. Max is right in pointing out weight as an important factor and his choice to turbo charge probably gained him 10-15 % efficiency. But to say this is "street legal" and implying an auto company could do this is just sad. The comment about auto companies not being able to meet 35 mpg "FLEET AVERAGE" would imply that the auto companies can or should control what people buy. The auto companies will reach that 35 mpg goal and more as gasoline prices rise. The marketplace will decide. If we see $15 a gallon gasoline consistently for the next few years, I'd predict that 35 mpg will be achieved in the 2010 model year. People just won't buy vehicles that get less. You won't have one person driving 80 mph down the interstate in an 8 passenger 15 mpg Suburban anymore. But the fact is many cars have been available for a long time that got better than 15 mpg, the customer just chose not to buy, instead chose to buy a 5000 lb / 400 horsepower sedan that would blow the doors off a 70's "muscle car" or a 4 door 4 X 4 pickup for the daily commute on paved roads.

8/1/2008 3:52:45 PM

This car was already built in 1981 nothing new this is just a copy

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