Instead of doing a bunch of research, i figured i would start here. I am trying to install a 66 289 factory 4v engine in my 75' 4x4. Truck was originally a 360 (4 speed granny low.). When i pulled it out of a field, found someone had switched over to a 78' 351m. My ????---what do i have to do to put this 289 in it. I know bellhousing is an issue. what are my best options and can i get a bell housing to bolt up to existing trans. if not, what trans assembly will be the best option. Many have asked, why the 289..because i can and gives me another 100hp and has over 300lbs torque and they sound SO GOOD.Plus this 351m is a pig. !60hp,lousy mpg and lousy heads/compression.any help from you experts is greatly appreciated. P.S. this is a 6 bolt 289 not the 5 bolt.

 

The 351M and 400 and 460 use the same bellhousing. You'd be far, far better off swapping in a 400 or 460. Or investing in a new intake, headers, and cam for the 351M you've got now. The 351M is sort of a Frankenengine and is badly choked from the factory to meet mileage/emission standards but has the same heads as a 351C. A 289 works fine in a Mustang but doesn't have the low end powerband to push a 4x4 truck around worth a flip.

If you're bound and determined you may be able to change the bell. I've got a T-18 bell to fit a SBF gathering dust. You'll also need to change the engine perches on the frame. I'd also recommend some 4.11 or 4.56 or 5.13 gears fore and aft depending on the tires you'll be running.

 

i had a 73 hiboy that i tried dropping a 351w into. ran into similar issues. got with either a 460 or drop a 390 in there or even perhaps a 300-6.

that year is kinds screwy since the frame is narrower then later years. you never mentiond what tranny you have? if its the NP435 you should be able to find a 300-6 bellhousing to work behind that 289. your next issue will be motor mounts that will require fabing up.

the 300-6, 360, 390 where the only motors standard for that year truck.

best of luck

 

300-6 uses the same bellhousing as 289,302 and 351w. havent got into setting the engine in there but wont be to tough to fab somthing up