Hi All
Trying to tune my basically standard 1600dp. It has new Kads with 009 dizzy. Trying to tune motor and all it does is run rough and backfires under revs(with the odd flame) Synccarbs, tried mixture and it makes little difference(tried different jets). Changed points, condenser no change. Tried a different coil same. Checked timing, ok. Adjusted valves, ok. Fuel pressure runs 1.5 psi. Plugs and leads are nearly new. Now I'm running out of Ideas what to check next??? Anyone got any suggestions??

Check disy is 180deg out, common prob

Timing looks right when I adjust the valves......

you are getting air into the inlet manafold with the engine running spray a bit of aero start or flyspray around eather side manafolds if it revs up you will have found your air leaki am asuming that the new carbs came with manafolds

have you checked your exhaust for leaks, like next to the heads.

what are you calling ok timing?
sounds like its retarded a few degrees, you want pretty much spot on 30*

I had a similar problem which was due to an air leak into the exhaust courtesy of the inlet preheat tubes. By changing to twin carb's did you seal up the inlet preheat tubes?

idle jets too small? pump jet set up ok? do a search for kadron tuning and you will find a really good site for basic setup and tuning