[Mgs] hesitation

[Malcolm Jeffcock]

well as some know I have installed a "new" engine which I must say is pretty good-compression of 150lbs across all 4. I have had electronic ignition installed and that's fine but I am having a hesitation problem. 

When cold its ok or driving around town with a constant variation of revs but once I start to cruise along with revs at say 3300 and then I try to accelerate I have hesitation, at time severe, it also seems to be brought on if I go up a hill as driving at steady rev level, it feels like it is only running on 3 or 2 cylinders when this happens, feels just like when head gasket went in the past. If the car is idling in driveway I can rev engine to high revs without a problem Could it be a situation of the fuel pump being able to provide enough fuel but not being able to respond to the additional demand for fuel as required for acceleration?

I should mention that the original SU pump was replaced with an aftermarket 3.5-5.0 lib pump...

I adjusted the fuel mixture to make it richer but that didn't help at all...any thoughts?

Malcolm