My Super 77 Diesel will fall behind the governor setting by over 100 rpm and not add much extra fuel to hold it as load is increased.  I never get smoke out of the exhaust unless it is totally bogged down.  

The only settings I see are the tension on the spring between the manual throttle lever and the govenor lever and a high speed stop on the governor lever.

Should I just increase the spring tension to get more fuel and then set the no-load speed down to 1650 or 1700 rpm or is there some other adjustment to make the governor bring more fuel in with less deviation from the governor settings (to try to hold the engine speed tighter with varying loads)?

Thanks,