I have a 78 F150 Ranger with a 400, C6, 9 inch combo.  The ol 400 is tired and is a 2 barrel fed setup.  I want more power, but have read that the best way to wake up a 400 is to do an intake, carb, cam, lifters, timing chain and roller rocker set up.  If I did all that, I'd want to rebuild it to ensure all is well on the inside.  With all that cost, would it be better to dump the 400 in favor of a 460 crate motor?  

When in doubt GO BIGGER.But i would stay with the 400 and just wake it up a bit. If you have the money for a crate 460 , and the time, ballence and blueprint the 400 you will get more bang for your buck............  

You can wake it up with just a cam and carb swap. Summit's part number 5200 cam works great with the 400's stock compression and heads. You can replace the 2 bbl carb with a Holley list #4412 500 cfm 2 bbl. Then add long tube headers.  

f-150 >460? a bit over kill? turning it into a monster hauler? if going bigger go for are "60 dana full flouter re.axle with hp. kitten-c6-]>thats a must!if racing a 9-N>does't [hum if not cheak the condition of your-re.>400 and build up to whats affordable for the use your projecting it for with in your costs.get good advice on your plans be realistic and then go for it and enjoy!the fruits of your labors.