351w vs 390
First what motor does your 78 have in it. 78's did not come stock with an FE (390 or 360, and others) but a previous owner could have put one in. If you have an FE in there already then swap in the good 390. If not then since the FE has a unique bell housing you will need to swap in the trans that goes with it. Not a problem if you have a complete running truck, but do you want to do all that work?
351W might be a direct bolt in and less work.
I chose to stay with the windsor and sale the 390 that I had.
My reasoning was that 390 parts are harder to find and expensive (at least from what I found).
I have had no problems finding parts for my windsor and there are a lot of relatively cheap performance parts.
Another factor is the 390 is a huge heavy engine compared to the windsor and I figure the lighter the engine the better balance/ handeling the truck will have.
Then finally, I just spend a bunch of money on rebuilding my windsor with go fast parts and am extreemly pleased with the performance. So I traded the 390 for a divorced T-case, crossmembers, and driveshafts so I can use my rebuilt c4 with the windsor in my 76 f-150 4x4.




