I'm finishing up a frame off restoration of a 1967 Lemans Convertible which has a year correct 326 w/ 4 barrel carb (New Edelbrock 1406), new distributor w/Pertronics Elec Ignition module, and backed up with a TH400 transmission. Engine has been tuned, all vacuum leaks sealed, timing set a 12 degrees, and idle at 850 RPMs. Engine is fine until I put the car in gear (Park or Drive). The RPMs drop about 400-500 RPMs, then fluctuates between these numbers, and sometimes dies completely.
Any help/suggestions would approciated.