you should feel it fall on its face when it hits the fuel cut - if you do not experience fuel cut you may have
1 max load screw too tight
2 sticking governor
3 hard shimmed spring capsule underneath the top cover
btw to the last piece of your information - in a diesel you need to spool the turbo first with engine heat then as soon as you hit boost the enrichment device on the pump (space ship sitting on top) presses downwards changing the max fuel delivery cutoff. The shove you feel is the excess fuelling burning in excess air in a very small chamber.
now if your pump has been messed with or a pump that is not suited/matched to your engine has been installed - it will not work properly.
your turbo should help to torque at quite low revs (1800 rpms) - and the pump should work with it all the way to the redline (4000 rpm I beleive)