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Smokey's New Hot Air Engine...THE NEXT STEP
Hot Rod
|May 2023
Smokey Yunick Has Devoted More Than Three Decades to Developing a System to Take Us to the Next Stage for Internal Combustion Engines. Now It's Ready.

SMOKEY'S HOT VAPOR ENGINE
Smokey Yunick builds a better internal combustion engine.
I was never a fan of GM's Iron Duke 2.5-liter four cylinder. Strike one: It was a four-cylinder engine. Strike two: It sounded absolutely terrible, especially in cars with automatic transmissions. The low-revving, buzzy four-banger came in nearly every front-drive car GM made through the '80s and into the '90s. It also came in S10/S15 pickups and Blazers and, more egregiously, the early third-gen F-cars. Tragically underpowered, they made far more noise than motivation. My opinion of the engine certainly would have been different if it had originally been designed and built like the version Smokey Yunick developed as proof-of-concept for his Hot Vapor engine theory. A radical change at the time, the gist was that, by superheating the incoming air/ fuel charge to more than 440 degrees Fahrenheit to fully vaporize the gasoline, engine power and combustion efficiency were greatly improved. In the working example Smokey built and Tech Editor C. J. Baker wrote about in the June 1984 issue of HOT ROD, the re-engineered Iron Duke was radically reenergized to the tune of 250 hp, 230 lb-ft of torque and netted more than 50 mpg. Why was this system never adopted into mainstream production? A rough speculation on my part says advancements in computerized engine controls and very precise fuel-injection designs provided many of the benefits of Smokey's theory with less of the added complexity. Check out the article and decide for yourself.
Many commonly accepted ways of doing things are based on tradition or opinion rather than sound engineering, physics, and chemistry. -Smokey Yunick
This story is from the May 2023 edition of Hot Rod.
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