Super Carbs
No web site focusing on fuel economy could be complete without at least paying homage to the legendary 100+ MPG Super Carbs, also known as Vapor Carbs. Over the last century there have been circulated urban legends of inventors able to extract fantastic fuel economy from normal vehicles. Some were a “mere” double stock mileage, while some — like the Pogue Carburetor — claimed over 200 MPG!
The common thread with all of them capitalizes on the fact that liquid fuel doesn’t burn; only the fuel that is fully vaporized can burn and contribute to power at the wheels. Many used exhaust heat, some engine coolant heat, others electric heat. Some used mechanical agitation, wick filters, vacuum, or other means of vaporizing the fuel. The earliest Patent I found was dated 1900 for a simple bubbler. Today’s electronically controlled vehicles, combined with EPA/CARB regulations render these inventions impractical. However, here is a brief description of just a few of the more prevalent ones. The following is posted “For Informational Purposes Only”, and not as recommendations. (See the History of Fuel Economy video.)
The Pogue Carburetor
Probably the most famous of the Super Carbs is the Pogue Carburetor, as it claimed over 200 MPG. This was Pogue’s 5th and final design (US Patent No 2,026,798, January 7, 1936) In 1936, inventor Charles Nelson Pogue drove his 1935 Ford over 200 miles on a single gallon of gasoline. This was witnessed by a representative from Ford Motor Company (D. F. Smith), Breen Motor Company (T. G. Breen), as well as an independent researcher, Mr. S. Stockhammer. Thus, it has demanded above average respect.
Rather large, it used 2 spiraling chambers that interleaved the fuel charge with exhaust gasses. The 2 would intertwine in the 1st chamber, then move to the 2nd chamber to vaporize even more. The original patent expired in 1953, which spurred much experimentation at that time. Cars Magazine ran an article on the Pogue Carb in their September 1953 issue (author I. T. Galonoy), which brought it back to the forefront.
The theory was that the hot exhaust gasses would exit the heat exchangers at close to ambient temperature. Fuel flowed in one direction, while exhaust gasses flowed in the opposite direction. However, the many folks replicating the patent in the 1950’s into the 1970’s never saw the gains claimed by Pogue. Researcher J. Bruce McBurney (who ran HIMAC Research until his death) claimed to figure out the secret — Thermal Catalytic Cracking (TCC). McBurney said the metal of the heat exchanger acted as a catalyst, cracking the larger fuel molecules into much smaller ones ranging from natural gas (CH4) to pentane (C5H12). Referencing Avagadro’s Law, this resulted in literally more fuel coming out than going in. The fuel would maintain a vaporous state at relatively low temperatures.
Pogue’s infamous test drive used the gasoline of 1936, which was distilled or fractionalized from crude oil. By 1939, gasoline was derived from a cracking process. There were more crystalline structured molecules in the newer gasoline (like iso-octane vs straight-chain octane), which are harder to crack. By the 1950’s, gasoline was “built” using cracked larger molecules, and by combining smaller molecules. Furthermore, tetra-ethyl lead was introduced into the fuel to cushion the exhaust valves and increase octane ratings. The lead coated the metal housing, and thus neutralized the catalytic properties. (This is why leaded fuel could not be used in vehicles equipped with catalytic converters.) The fabled Winnipeg Carburetor is this Pogue design. Curiously, Charles Pogue ran an oil filter factory most of his life. (Check out our Pogue video as well.)
The Ogle Carb
Tom Ogle’s design (US Patent No 4,177,779, December 11, 1979) was very similar to Pogue’s 1st patented design (US Patent No 1,792,239). It converted the fuel tank into a fuel vaporizer. Engine coolant was circulated through a jacket to counteract the cooling effects of the vaporizing fuel. Baffles and filters bubbled air up through the fuel. A series of filters dried out the vapor so the engine would only see a dry vaporous fuel charge. Ogle drove 104 miles on a single gallon of gasoline in a 1970 Ford, with cameras rolling, and experts all around.
Ogle sold the patent to a retired US Navy Admiral with “more money than God”. In a private phone interview in 1999, the engineer hired by the Admiral disclosed the challenges of bringing the Ogle design to market. This engineer (name withheld by request) said the Admiral (the engineer claimed the Admiral had “more money than God”) wanted to pursue this as his legacy. He hired the engineer to get it to market. Mr. Engineer said they were able to get far better fuel economy than Ogle ever claimed — but only on the first tank of fuel. The second tank delivered maybe half that. The third tank was back to stock fuel economy, but with drastically reduced power. By the 4th tank, the engine barely ran. The only solution was to replace/ clean the filters at each fill-up. This pretty much eliminated any ROI gains from the system purchase. The company eventually marketed retrofit EFI systems for older vehicles. (For more, check out our Ogle video.)
Smokey Yunick
Henry “Smokey” Yunick ran “The Best Damn Garage in Town” in Florida, wrote many books on performance, and was famous as the guy that won many races by ingeniously “not cheating” by splitting hairs with rule book wording. He was a godfather of Small Block Chevy performance. He also developed his “Expander Cycle” engine, pictured.
He applied his Expander Cycle principle to a Pontiac Fiero, Plymouth Horizon, and a European Fiat. It was a staged vapor system that included a turbocharger. A carburetor was mounted above an HVAC heater core, which served as the 1st stage of vaporization. The second stage was a turbocharger (homogenizer/check valve) with the intake scroll wrapped in an exhaust-heated jacket. Finally, the mostly vaporized charge was ducted to the combustion chamber through an intake manifold sporting an outer exhaust jacket. The final stage exhaust jacket was temperature controlled to maintain around 435-440 degrees F. An exhaust bypass valve would prevent excessively high intake charge temps. Since air expands when heated, Smokey referred to his turbo as a “check valve”, or compensator. He achieved around 250 HP at 50 MPG on both the Fiero and Horizon. This was quite remarkable in the 1980’s.
In addition to the induction and exhaust system modifications, his design required extensive internal engine modifications. Relevant US Patents include: 4,503,833, 4,592,329, 4,637,365, and 4,467,752. Upon Smokey's passing, his historic "stash" has been mostly liquidated. The origional Plymouth Horizon has been resurrected, and many of the engines, camshafts, and other unique parts are now in the hands of private collectors. Daniel at Hill Country Performance & Machine out of Texas is one such collector. He has posted several videos on Smokey's Adabiotic Engine:
What ever happened to Smokey Yunick`s Hot Vapor Engine
Taking Apart Smokey Yunick's Hot Vapor Engine Part 1
Taking Apart Smokey Yunick's Hot Vapor Engine Part 2
Ray Covey
Covey used exhaust heat to vaporize the fuel. The vapor chamber had several spiraling coils that routed hot exhaust gas. An injector sprayed fuel onto the hot coils. His system resembled dozens of others including the Sgrignoli, Nichols, Beasley, and many others. Some used exhaust heat like Covey, while others used engine coolant to vaporize the fuel. Of all the Super Carb designs, this is the most common. Some of the inventors tried to manufacture and sell their designs, while some wrote books and/ or offered seminars so “you could build your own”.
LaPan
Ted LaPan took clues from the common swamp cooler. His design shared common traits with the Tucker, Lambert, Miller, Nay (pictured), Wallace, and other designs. The concept was to wet a filter with gasoline, then draw air through the filter. (For more, watch our Allan Wallace video.)
Baldwin
Joseph Baldwin used high vacuum to vaporize the fuel (US Patent No 3,630,698, December 28, 1971). The high vacuum concept was used in many designs, some augmented with engine coolant or exhaust heat. They capitalize on the fact that liquids boil (vaporize) at lower temperatures when placed under a vacuum.
Naylor
Father & son team, Loren & Kelly Naylor devised a staged vapor system with progressively hotter stages. It starts with a carburetor (see image below). The air/fuel charge then pass through a heat exchanger heated by engine coolant. The 3rd stage conditions the fuel charge with an exhaust gas heated exchanger. The Naylors wrote a book and conducted live seminars across the US, teaching folks how to do it themselves.
Production Carbs
Remarkably, there were a few fuel efficient carburetor designs that actually made it to market. Here are a couple:
The Fish Carb
The best known is the Fish Carburetor. Introduced in the 1940’s by inventor Robert Fish, it incorporated several unique features that consistently delivered a 50% increase in efficiency, with dramatic improvement in power. Instead of an annular booster, it discharged the fuel from the throttle shaft. Replacing the jets/metering rods was a variable depth pick-up arm mounted in the bowl, connected to the throttle arm. The design was so good, it remained in production into the 2000’s. However, production shifted from the original Fish family to Leonard Reese & Company (UK), to Mike Brown, and eventually to Rich Ackerman. Ackerman bought the molds from Brown, but quickly became discouraged by the poor quality. He re- invented the Fish Carb, fixing plaguing deficiencies in the original design, and added his own innovations to improve it beyond anything that had been seen previously.
The Predator
The Predator Carburetor is a Variable Venturi design. Ford Motor Company used an innovative (albeit cantankerous) Variable Venturi Carburetor on the 1981 to 1983 Lincoln Town Car, delivering over 30 MPG from a large luxury car. Rumor has it the Predator was originally designed as a fuel economy carburetor. Allegedly, after threats from some dark powers, it was redesigned to deliver physics-defying power, but consume copious amounts of fuel in the process.
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MPGenie Basics 051 Training - Fuel Economy History Introduction
MPGenie Basics 051 Training - Fuel Economy History Video
