Robert,
I suggest you start a new thread for us to discuss your conversion ideas, think of a suitable title that describes your ideas or the ideas you are looking for.
I'll quickly answer some of your questions here first.
8V71 is probably much to heavy for your truck, and to large to fit. But there are a number of smaller Detroits that should fit. Just a guess, but if you were able to stuff an 8V71 in a 15,000 lb truck and trailer at 70 mph fuel mileage would be single digits, 8 or 9 if lucky, again, just a guess.
What size truck do you have?
I don't consider a Detroit a dirty engine. Perhaps people are thinking of emissions, in good shape with some of the better injectors they don't show any signs of being dirty. They have a partly undeserved reputation for leaking oil. With proper assembly techniques a Detroit won't leak a drop. They do have air box drain tubes that will dribble oil, (usually from bad blower oil seals) this is part of the design, if it offends you catch cans were made to capture this oil for periodic draining.
A DT466 from all I have heard is a good engine, I see nothing outstanding or special about them though.
If you want a diesel pick one that you like for a number of reasons, right or wrong you need reasons to suit yourself.
I chose a Detroit for my truck because they are somewhat different being two cycle with a blower and mine has a turbo. They are extremely reliable, easy to get parts for at very fair prices. They have been around essentially unchanged for 70 years, that says a lot about the quality of the original design. most all parts from a 71 series made in 1938 will fit the same engine made in 2000 (last year sold to civilians). Detroit's are very simple in operation, construction, and easy to service.
Start a thread about your plans and see what happens.
Grigg
