Newly rebuilt 200 with a comp 252 cam. Only have 12lbs of vacuum at idle due to cam I guess. I only see my timing go up about 2 degrees when I hook up the vacuum line. When I advance the throttle I see no more movement. Is it because of the cam and low vacuum? If I suck on the carb end of the dist vacuum line the advance does move but that is all I know. Will this load o matic work with a cam installed?