This is a how to on how to build up a 4D55 motor. Over the past 2 years, with the help of my good friend Mike Warme, have made several modifications and improvement to the 4D55 that have not only improved it power, but have also improved its reliability and durabilty. Most of the modifications are direct boltons from Mitsubishi, but there are a few which are custom modifications.

Here are the improvements:

EGR and California emmisions delete
4D56 Head w/roller rockers
Ported and Polished head and manifolds
Watercooled turbo conversion
1983 injection pump swap
Custom Brake Booster
Battery relocation Setup
Water Pump Upgrade
Pyrometer
Boost Gauge
EHM
Custom air intake
Intercooler

I will try to post how to articles as fast as possible, but I work full time and I am a full time graduate student so it just takes time.