what modern v6 engine can i put in a 1973 f100 ?
Yes but you would need the wiring, emissions system and computer.
A 4.2 from a F150 might be what you want.
A 3.5 ecoboost coud really make your truck fly. But it is true u would need the harnesses and computers. I’m currently in the proscess of transplanting a 2013 5.0 coyote into my 68 f100 I had to get all new engine harness computer and trans harness.
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