CDA 455 said:
Damn, damn, damn

!!
What set up would you recommend for towing with a Cummins?
It appears that kind of performance is race-oriented.
Easy on the fuel and especially easy on not having a too large of a turbo.
Thats the beauty of a diesel that is governed by fuel flow and not air. Even though you can lay down a nice 650HP on the dyno, it doesn't mean you have to neccessarely live with that in stop and go traffic. You can only apply say 200HP with the position of your foot. Then, with air being cost free it doesn't matter how much of it you need. That means you can run the stock radiator and cooling system, bottom end of the engine, etc. With a huge gas engine, it's going to use so much air and you've got to pay for that fuel that it needs to match that air regulation.
Towing... a 400HP truck tows really well. Good ingredients IMHO would be a fairly large fueling box like an Edge Comp box, Juice, TST, etc. A turbo in the 57-62mm compressor wheel with an 80mm exhaust side is pretty nice for towing. It'll keep the EGT's in check with 400HP worth of fuel, yet still retain a decently fast spool up to make towing possible. The bigger turbo's and bigger injectors don't tow very well because they like to smoke bad, have a hard time spooling from the extra weight not letting the engine climb in RPM as easily, and when the big turbo spools finally, it can want to surge and make the truck really take off. Not any too smooth unfortunetly.
That is basically the setup that I have, minus the 57/14 turbo(maybe if I win the lotto

) which is much much milder than Demon's setup.