diesel tubos work in the same principle as a petrol one but doesnt create the vacuum in effect. its long boring process of explanation!!!! as long as its got an air feed, boost pipe to engine, exhaust feed, exhaust oulet and a wastegate your good. to gain an extra 20bhp, turn up the max fuel screww within the pump. adjsut the "on-boost" fueling and turn up the turbo pressure. in the link above theres other links to a video on youtube for tuning a td pug but the principle is the same for the td escort. for a good 140bhp+ get an fmic.