Okay, i purchased an Old f600 1978 dump Truck has a 391, thats an educated guess. Blew a gasket over heated the engine cracked the head. I want to either fix the engine or replace. I've been told that the engine is likely shot and will not run long with the head replaced and reworked. I've been told of an engine that I can purchase that will "likely" fit it. It's a 460. I need to know whether it will swap or what to look for so that I can identify whether it's a fit or not. Thanks

 

The 460 will not bolt up to the existing bellhousing, motor mounts, etc.

You COULD get all the stuff for a 429 for that truck which is bolt-for-bolt like the 460, and make it work. But it's a lot of work. My brother once put a 429 into a '68 F600 that had a 330 originally. It was a lot of work, and he was able to buy all the parts direct from Ford, but even still, it was a big expense.

The easiest thing for you to do is a 391, 361, or even if you had to, a 330HD (which is a gutless pig and would be enough to make it move but not much else if you're moving heavy loads).

Another option is an FE engine (352/360/390/etc), but the exhaust would have to be reworked, and the motor mounts on the timing cover would also be another issue that would have to be overcome because of the difference in the crank snout.

Your existing 391, if it was bad enough to crack the head, the bottom end is probably gone as well. Cylinder walls and pistons scratched, bearings toast, etc. A full rebuild would be in order.

Oh, and WELCOME to FTE!

 

Thanks for getting back with me. I'm expecting that it wouldn't fit. I've been looking for a replacement and cannot find one within a reasonable distance. Any idea where I might look?

 

Serving suggestion:

Rebuild your motor. It will probably clean up at 30-10-10. Not a cheap prospect, but it will be less fuss than a conversion.

I think you can swap the top end for FE stuff if need be. Otherwise, FT heads are out there--just a slog searching them out. But if your block is good, it will certainly take a rebuild.

If you are super lucky your bores will clean up and you can stay with your pistons and add new rings. Ditto the mains and rods; if they mic out good, new standard bearings and away you. That is a major long shot.

New oil pump and gaskets and you're back to 70% plus. ymmv