Looks like 2 twelves with a shared exhaust stack between them. I would be loud. As I recall that one became a kite during one of its runs. Lot of go juice.
Growing up in the Detroit area, I vividly remember the thunderboats, when they used to use the Rolls Royce Merlin engines or Allison engines, you could hear them ten miles up the river in Grosse Pointe.
Now they’re all turbines and much quieter. When they were thunderboats, if you were close, the ground would shake as they went by.
Those are Packard-made Rolls-Merlins, 12 cylinders.
Anyone remember a guy named E.J. Potter? Back in the early ’70s he put the Allison version – the predecessor to those Merlins – in a ’59 (or maybe ’60, can’t remember) Plymouth and drag raced it.
Way back in my yoots, I remember a Hot Rod Magazine article about a guy that put an Allison V-12 in a ’65-ish Chevelle. it took 4 Carter AFB’s to feed the thing and he ran it through a 2-speed PowerGlide.
I’ll bet that PowerGlide was held in with Dzus fasteners to speed up the frequent transmission changes.
Bustednuckles 
Gotta know sign language to run those wide open..
😵
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Phil, I couldn’t tell if those Packard engines are 6 or 12 cyl engines
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Looks like 2 twelves with a shared exhaust stack between them. I would be loud. As I recall that one became a kite during one of its runs. Lot of go juice.
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Growing up in the Detroit area, I vividly remember the thunderboats, when they used to use the Rolls Royce Merlin engines or Allison engines, you could hear them ten miles up the river in Grosse Pointe.
Now they’re all turbines and much quieter. When they were thunderboats, if you were close, the ground would shake as they went by.
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Those are Packard-made Rolls-Merlins, 12 cylinders.
Anyone remember a guy named E.J. Potter? Back in the early ’70s he put the Allison version – the predecessor to those Merlins – in a ’59 (or maybe ’60, can’t remember) Plymouth and drag raced it.
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Way back in my yoots, I remember a Hot Rod Magazine article about a guy that put an Allison V-12 in a ’65-ish Chevelle. it took 4 Carter AFB’s to feed the thing and he ran it through a 2-speed PowerGlide.
I’ll bet that PowerGlide was held in with Dzus fasteners to speed up the frequent transmission changes.
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The 3406B isn’t too shabby either, just a different application.
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That is the Spitfire philosophy – build the smallest airframe or hull around the biggest engine you can lay your hands on and go for it! >};oD
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See also: Plymouth Roadrunner, Chevrolet Camaro.
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We used to go to Lake Coeur d’ Alene to watch the races (in the late 60’s and early 70’s)
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