I have a 74 F250 4x4 Crew Cab with a tired 360 mated up to a C-6. Was thinking of puting in a 460. What all would I have to do to make it work? I know motor mounts but what else? And is it worth all the money and effort or should I just put a new (remaned) 390 in and call it good. All the post seem to say I could get better MPG with a 460 than a 360 or 390, how true is this? Thanx for the help.

 

I have a 74 F-250 4X4 with a 390 FE. Personally, I would go with the 390 FE it is a good motor and you can modify it all you want to make the power you need. All you need to do is find a 390 crank and rods and just reuse your block. The 360 and 390 used the same block just different crank and rods. You can also buy a stroker crank which is what I am considering buying, it will increase the cubes to about 445c.i. However, the 460 has more aftermarket parts and will serve you just as well. If you swap to the 460 I believe you will need a new bell housing to mate up to the C6. As for the fuel mileage I honestly do not believe it has any real bearing on which engine you use. There are just too many variables to consider. That is unless you use a 460 with fuel injection, if fuel injection is used it would increase your fuel mileage to some degree. If you consider using the 390 go to the 332, 352, 360, 390, 410, 427 forum and look at the power you can make with a slightly modified 390. Its definitely worth the look.

 

Since you have a C6 trans you will need to find a completely new trans. As for which motor I would go with? I am a 460 guy and have had great luck with them. I have always gotten better MPG over the 351M/400 motors. I never owned an FE motor but had friends that had them in their trucks. Their MPG seemed to be worse than mine but who knows for sure. In the long a 390 will give you great power and be cheaper in the long run.

 

If you do not have the 460 already, it will cost more to go that route, in $$ and downtime. The 460 will need it's own C6, or you can find a case and swap in the internals from your current C6. A well tuned 390 will run just as nice as the 460 and mileage will be close. You will also be able to pull and replace in a day....

Just my $.02's --Mike