Mine used to get up to 80 quite quick, for what it was but took and age to accelerate after 100, make sure you use a genuine DELPHI filter, and shove some MILLERS diesel system cleaner in there, this is by far the best cleaner I ever used, use bio as well, as this defo perks it up.
I founf a lot of pattern fuel filters would not flow as well as the genuine dlephi ones, and held mine back a bit, a noticeable amount, and every little helps, also up the full pedal stop on pump, as they can take much more revs.
tabetha