Only the 110 1.6 jumps to 145 ish on the C4. The 92hp (as it is on the C4) jump to 110 - 120 with a remap on the lower spec diesel. Not sure exactly what differences there are though and if it is easy to change a 92 to a 110.
aye although the hdi engines and the tdci engines are the same, ish. for some reason ford get very slightly less power out of them. (only a couple bhp)
the zetec-s has the low output enigine (90bhp ish) as the basic c4 like the sx/vt.
My c4 has the 110bhp version fitted to the focus ( the 90 is fitted to the poverty spec focuses). i think the main difference is the 110s have an intercooler iirc. and different air box etc. dont think there is much difference internally.
Mapping the low ones as wozza says gets you 120, a box is probably good for 110ish, the higher out put ones, a box gets you about the same output as the 2.0l deisel, and a generic map gets you about 140-145, but a custome RR set up map could get almost 150.
hows the smoke on the TB, they tend to make your car a fog machine because of how they work. i only really get smoke if it drop it too low and get the revs too high. but torque and boost is fawsome.