Seems to me, there is a big misunderstanding between bragging right horsepower, and a truck engine.
Who gives a flying frick if your truck goes up the hill at 45, instead of 55 like the cummins? Truth be known, my little 318 in my dually, running 4000 in second gear, can pass most older diesel trucks loaded the same.
A 318, with the right gears, will do just fine. (Chryco is right about the short box though)
Last time I checked, the "real" trucks of the 60's came standard with 6 cylinders. Why? Becasue it is a truck! Yup! Not made to go fast.
318, with 3.91 gears, will pull JUST FINE. Might be a bit slow, but, will do just fine. Trust me, I do it almost every day.
Having a 318 is a bad reason to sell it.
305 HP & 930 Ft lbs TQ
Question? How did you get 13 less HP, and 30 less pounds of torque, than a "318" detroit 8V92? From a 360 cu in cummins?
"92" is the cubic inch per cylinder, so the detroit would be 736 cu in.