DO NOT RUN MORE THEN 40% meth on your truck... Diesels are differant then the gas rigs you are used to.
Get some normal gauges... I recomend Isspros from
DieselManor - Taking the Mystery out of Diesel Performance™, and a overboost eleminator from
ITP Diesel, L.L.C..
Keep your wastegate working, anything over 25-27#'s boost and the turbo will not be happy.
Look
HERE for water injection...
Without injectors, and turbo upgrades you will never get near 400hp. But be careful with the water injection, the 400hp mark is more of a Cylinder pressure deal then a HP deal and lots of meth equals blown block...