I have a 1977 F150 Ranger XLT 4x4 short bed, it currently runs a 400/C6 combo, I am looking at swapping the 400 for a 7.3 diesel, is the swap worth doing? Will I gain a better mileage than the 400? How will it compare powerwise?
Cheers,
Shane

 

It will get better mileage then a 400. I have never driven a 400 so I dont know whar they make for power, but the 7.3 will probably be slower if it is still NA. Keep in mind you can safely figure 1200lbs wet wight on a 7.3 so that is a bit heavier then the 400.

 

First i would not put this engine in a half-ton, unless you are planning on going to 1-ton running gear in the least. After that, i had a 400 4spd in mine, had edeljunk carb and intake, timing chain set (0*) and a DUI dizzy. As far as power, speedwise they were about the same but nothing alike in how they do it. Pulling wise, you could put 2 400s under the hood and it wouldnt touch the idi. With the 400 i was getting 8-11, with the NA IDI getting 17-20, now with it turned up and in need of a tune im averaging 15.5ish with the turbo and a foot of lead.

 

I appreciate your answers.
Down here in New Zealand I have increased rego for a diesel, plus I have to buy mileage, and those two combined make it not wrth the swap, but I appreciate the answers.
Shane