Good question Dennis, and I really don't have the answer. Just a marketing decision I guess which deviated from the previous methodology.
The standard 2bbl 283 was known as the Turbo-Fire unless a 4bbl version (pre-'62) was ordered, and then it was a Super Turbo-Fire. The carburetion difference added the "Super". The 348 "W" engines were Turbo-Thrust in their basic form, and then with 3x2s added, they became "Super" Turbo Thrust. The "Super" was also used on the 305hp hi-perf engine with an AFB carburetor (although still with a hydraulic cam). With the addition of a "special" cam, (meaning solid lifter) they became Turbo-Thrust Special. And in the case of a tri-power solid lifter 348, they were known as the combination "Super Turbo-Thrust Special". Now, that's a big name to throw on an engine.. So "Super" meant a carburetion upgrade while "Special" meant a cam upgrade.
In '61 when the first 409 was introduced, it was simply called "409 cubic inch engine", with no "name" what-so-ever.
In '62 (for whatever reason) Chevrolet reverted back to the Turbo-Fire name for both 409s (380hp & 409hp). Even in '63, all 3 engines, including the 340hp hydraulic lifter engines were only called Turbo-Fire. Who knows why????
In Chevrolet's published introduction of the new '62 models, they stated, "The name Turbo-Fire is applied to all 1962 Passenger Car V-8 engines and on the rocker cover decals it is followed by the engine displacement figures". That's it. They dropped the individual names for each engine.
Verne
