Using nitrous in a few vehicles I have owned in the past (not a diesel, but should be the same principle), timing is a huge issue, especially with larger jets are put in the equation. Nitrous would not be a bad idea for cooling an intercooler (if you want to intercool it, that would be a start to see how she responds to sudden temperature changes), and the newest "cheaper" alternative is CO2... However, CO2 contains unburnable moisture that could detnate an engine, that's why it's only kids with Honda Civic I see using these systems at the track, and a lot of those kids couldn't tell the difference between a ratchet wrench and a hammer... There are basic mods that I plan on trying in the future, such as larger intake plumbing with better flowing air filter, porting down-pipe from turbo (cast, so be gentle), I am waiting for pyrometer and bost gauge so I can play with IP, and maybe sitting down and actually crunching the numbers to see what kind of turbo I could put on there that would actually add hp and torque, so far one from a 7.3 powerstroke Ford pickup is the easiest to deal with, and plenty of aftermarket goodies to go from mild to wild with. Getting good hp and torque rating out of a multi-fuel would include a complete teardown, re- blueprint, custom internals and externals, possibly running a stand alone ECU (Engine Control Unit, Megasquirt makes universal programable ones, but takes months if not years to dial in if you have never programed or flashed one prviously)...
Here is a good starting point of easy and fairly cheap mods to do without the use of the juice...
Air Filter (K&N will make custom filters, or mount an 8" one directly to the mushroom and eliminate the inline filter (no more water fording)
Increase the diameter of the intake plumbing itself, no PVC or polished metal as this will increase intake air temps, cold air is more dence which compresses better... Make that pig breathe...
Exhaust will lower exhaust temps with the RIGHT size diameter... 5" diameter is a good starting point, with mandral bends and no restrictions... If she takes bigger breathes, she can stride a little quicker
IP (Injector Pump), If she's breathing beter, she might need a bigger drink, but she'll start blowing coal...
Larger injectors can be done, but I don't know the stock CFM, so I couldn't even start to give you a figure for that, but might wanna look into a fuel pressure gauge and regulator... Thick black smoke will roll from the stack, and that prius next to you will hate you...
Lighten the load... Lighter is quicker...
Now, remember these are all basic "old school" drag racing tips of the trade, as I have been in that hobby for over 10 years. These big ol' trucks are not sportscars, but i'm sure geting to 65 will be a little bit better, but the more hp and torque, the more chances of catostrophic meltdowns can occur... Nitrous and propane would on these, in my opinion, would be like putting an elephant on steroids and crack... It sounds like a fun day at the zoo, but in the end a lot of tears and pain would result in the end
