This is an original American LaFrance Junior V12, but don’t let the word “junior” in the name fool you into thinking it’s a small engine – it has a displacement of 527 cubic inches or 8.6 liters.
The reason this is called the Junior V12 is that American LaFrance had an even larger V12 in production, with a displacement of 904 cubic inches or 14.8 liters. The reason for the size of these engines is that they were used for powering fire trucks, including their high-volume water pumps.
The origins of the American LaFrance Junior V12 are said to lie in the Auburn V12 that debuted in 1932. The Aubrun engine was developed by Lycoming of Williamsport, Pennsylvania – with both Auburn and Lycoming belonging to wealthy industrialist E.L. Cord.
The engine was developed by George Kublin and known at Lycoming as the BB V12. It’s an odd looking engine to say the least, with the narrow 45º V-angle, the sideways spark plugs, a “fire slot” combustion chamber, and for the fact that both the intake and exhaust manifold are above the engine.
The Auburn V12 had a displacement of “just” 391 cubic inches (6.4 liters) and it was capable of an impressive (for the time) output of 160 bhp at 3,500 rpm. The Great Depression would kill off the Auburn marque and nearly the Lycoming V12 with it, a savage blow to the company as they had spent a reported $1 million USD developing it – the equivalent to over $23 million USD today.
The version of the engine that was used by fire truck manufacturer American LaFrance was almost exactly 35% larger than the Auburn/Lycoming BB V12 and as a result the power output was similarly increased, up to 216 bhp at 3,500 rpm – exactly 35% more. Torque was almost double this figure, with 400 lb ft reported by most sources.
There were a number of changes other than just the size, the engine was also given twin spark plugs per cylinder and dual-double ignition systems with four coils and four distributors, this was to help improve reliability as the engines could run with only one of the ignition systems functioning.
American LaFrance would keep the engine in production for decades, using them in countless thousands of firetrucks. Today there is a small but dedicated group of enthusiasts who keep these engines running, some have even converted fire truck chassis into oversized roadsters – vehicles that never fail to gather a crowd at shows.
The American LaFrance V12 Shown Here
The engine you see here is an American LaFrance Junior V12 that is in largely complete condition externally, but the internal condition of the engine isn’t listed. It has the intake and carburetor in place as well as the exhaust manifold, both above the engine of course.
It’s finished in bright green and the two spark plugs per cylinder are in place, but the distributors, coils, leads, and several other parts required to get it running are currently missing. It could make an excellent project for the right person, potentially in the front of a hot rod.
The engine is now due to be sold by Mecum on January the 17th in Florida. It’s being offered with no reserve price and you can visit the listing here if you’d like to read more or register to bid.
Images courtesy of Mecum
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