Sounds like the engine is not advancing the timing quick enough since the vac advance is disconnected. Look to see which distributor you have, if it has the last 3 digits as "050" you are in good shape. Look on the
www.dgi.net/914/ site under tech reference and then under distru\ibutor chart. It give you the specs on different distributors. I've heard the 009 is bad news, however it is still probably better than what you have set up. If I were you I would hook up the vac advance somehow, this "should" really help your low end.