Wally, Keep in mind that the ideal position described is how the carb. was designed to operate in O.E.M. conditions. Now we are using them on different displacement motors, with gas of different B.T.U. & burn characteristics, maybe cam grinds, valve size, head porting, headers, etc. all affecting cylinder filling. So, setting it 'by the book' may not give the best results. Then, if its either lean or rich most all the time, try changing the main jet size. They are the same as AFB models, means aftermarket Edelbrock is the same & these are all easily available. Many times it'll be OK cruising but hesitate, means lean, when accelerating like passing other cars. IF we had an assortment of metering rods, we'd try a smaller 'lower' Diam. rod. Not having that, what can be done is just bend the M.R. arm so the rod is slightly higher up. A small change will have a marked effect. Doug
