I had to look it up on Wiki, I hadn't heard of them either. They actually made a 478 ci V6 which I've never seen in any car auctions. Makes me wonder if they were prone to catastrophic failure or something. Maybe the 6500 became tractor trailers?
478
The 477.7-cubic-inch (7.8 L)
478 was one of the largest V6 engines ever built. Gross output was 254 hp (189 kW) at 3700 rpm and 442 lb⋅ft (599 N⋅m) at 1400 rpm. Bore and stroke was 5.125 in × 3.86 in (130.2 mm × 98.0 mm). It was introduced in 1962 for the 6500 series trucks.
Internet is wonderful
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