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I'm strongly considering doing a 4bt swap on my 78 f150 4x4 351m 4 speed. I'm looking for info on the swap who on here has done one what parts will I need. Are there any good detailed threads on it. I know a zf5 is the preferred trans for the swap but I'd like to keep my np435 for now if possible will the clutch I have a new clutch for the 351m will it work or will I need to source a different one. Any info you guys can provide is greatly appreciated thanks
 

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351M clutch may or may not swap. You'd need to try it and see if it fits a Ford Cummins flywheel. You'll need a small block Ford bellhousing for your transmission. Ones found on a 300 I6 or 289-351W engines would fit the Ford Cummins adapter plate. What gear ratio do you plan for the differentials? The highest available in that truck was 3.54 in the Dana 44 high pinon. With a 31" tire you'd be turning 2310 RPM @ 60 MPH. The engine can do that but the fuel mileage will really suck. Ideal operating RPM is in the 1700-2000 range. Most shoot for 1800.
 
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