I have a 1980 F150 It curently has a I6 That is wore out I have large tires and would like to have more power I have the whole front end of my truck and canot decide wich motor I want to put in it I want a big block and am leaning toward the 390 but don't know what I might run into I know they didn't put them in that year of truck and do not know if the bell housing will bolt up to my tranny. any help would be great..or other opionions on other options such as 400m 351w or 460

 

Since you are making such a radical change from stock, I'd probably go with the 460 setup. It's hard to beat the 460 for overall power/torque and parts are readily available and a little cheaper than the FE's. You'll have to go to a salvage yard and get the motor, trans, perches, etc from a factory equipped truck.

 

I converted a 76 F100 from 300-6 to v8 but am not that familiar w/ the 80 and up frame. The only transmissions that will bolt to the 390 are FE bellhousings from the FE family. Your 300 tranny bellhousing would bolt to a 302 or a 351W.... will not bolt to 351M,400 or 460's or the FE's (352,360,390 mostly in trucks). I know that in my 76 the radiator for the 6 had it's inlets and outlets on the opposite corners from the V8 radiator, and the 300 sat on it's own frame perch. I had to get different frame perches for the 302, and I'm about to drop a 390 in it, so it's getting yet a different perch. The 360/390 ceased production in 76. I have heard of ppl putting 390's into 80's vintage, and even stupid stuff like into a late 90's Mustang. But you may have legality problems w/ that sort of conversion. And you might have to get creative about frame mounts. The 80's vintage came w/255,302,351W,M ... 400 460 in v8's
I would discourage you from putting a 302 into it. If you want to keep your tranny, you will have to go 351W,302. C6 automatics have integral bellhousing patterns in Smallblock bellpattern.. 300,302,255,351w,351C. The FE's have their unique pattern and the 351M/400 and 429/460 share a pattern. I don't know much about the diesel. I'd say that building a 460 would be cheaper than a 390.

BBT

 

I love FE blocks and I love my 390 in my 1970 f-100, but please do yourself a favor and go with the 351W or 460. Like stated above you will have to get a different tranny if you go big block, but trust me that parts, especially performance parts, are much harder to find and way more expensive for the 390. Cube for Cube the 460 makes more power and probably lasts longer. If it were me I would soup up a 351W. Parts are really easy to find for them and they make great power. Save money on the tranny and put it into the motor! From my own personal experience the 351M/400M aren't a motor that I would change to, but some may dsagree.

 

BBT i see what your saying ...,but how do you expect to fix the engine mounting problem on the 390... oil pan hits crossmember... motormounts dont line up and all the problems that im haveing..... MAL20000

 

I think what I said Mal, is that I've heard of the 390 into 80's pickup being done, but that some custom work had to be done as far as the mounting perches ect. My point was to discourage the conversion in favor of one of the engine types that came in that era, particularly the 351W.

BBT

 

 

My 73 f100 came with a 240 and a 4 speed. I changed it over to a 302 and c6. I had a 75 f250 with a 390. This 302 just doesnt make the torque that my 390 made. What is the popular oppinion on getting more torque to the rear wheels? I can get a 360 (which can easily be converted to 390 or 410) and c6 to fit it pretty cheap. I can also pick up a 351 windsor well in my price range. Which way would I be better off? My 302 already has 69 model boss heads, 83 model mustang aluminum manifold, crane energizer cam, holley 600, and electronic ignition. There's not much more I can do for it.