MG Car Repair: MG B, facet fuel pump, wiring loom

Question
Recently rebuilt engine on my 69 B, also new wiring loom. Car runs, but hunts a
bit on idle and under load goes in fits and starts--doesn't quit, just jerks along.
Car has no emission controls, 2 Sus, Mallory dual point, peco headers, facet fuel
pump . I have tried a second spare set of Sus--same problem. I'd be thankful
for your advise, Jake

Answer
Hi Jake,
Any time I have an engine that "hunts", I try to make changes to isolate the problem into a smaller area. Like try to richen up and lean out the mixture to see what changes you get. Then try to change timing back and forward and note any changes. I am not familiar with the Mallory dual point system but I believe you can disable one set for test purposes. Try the standard test for a vacuum leak by slowly restricting the air intake to each carb and look for either a smooth out or increase in RPM.
If the Mallory has a vacuum advance try pinching off the vacuum line.
Put a timing light on it and at idle try to note if the timing is changing by preceding or trailing the RPM increase in the hunting. Sometimes you can tell if the timing is causing the ups and downs in RPM or is the result of the the RPM change.
It is more difficult to find these types of problems on an engine that has modifications.
Let me know,
Howard