Also known as the Cooper RV/RB engines. RV = early, plain main bearings; RB = late, ball mains.
Cooper Engineering Co. [who later became Sunbeam Corporation] were the actual manufacturer.
Several online sources say that these were a Johnson Iron Horse X-500, made under licence.
Cheers,
Gadge
"ODK Mods can explain it to you, but they can't understand it for you..."
"Crazy can be medicated, ignorance can be educated - but there is no cure for stupid..."
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