I know it's not a "truck" engine, but don't forget the T-4 from the early sixties Pontiac Tempest. It was half of a 389, which was 3.75" stroke. Crossflow head.......
. Not a great engine overall, but an interesting concept to "morph" another design to get a desired result. Just look at the Chevy 4.3 V6. Just a 350 with the front two cylinders knocked off
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