Hello Everyone,
My Datsun ran yesterday for the first time since the summer! I have swapped out the old A10 for an A14 bored 1mm over, with stock cam, MSD ignition, A15 swirl-port head and exhaust manifold, and a set of SU-type GX carburettors.
The engine seemed to be running okay... no exhaust past the manifold though, so VERY loud!... I had to fiddle with the adjustments on the bottom of the carbs (the jets, I believe) and the timing and it was running best at about 15 degrees BTDC, but the carbs didn't seem to be working too well. I had gone through them and installed new gaskets, fuel bowl valve, cleaned them out and made sure that the needle didn't bind when the piston moved up and down. I also added 20w oil to the dampers, which I read was the right weight on the internet, but it seems quite heavy! The carbs were doing some backfiring, and coughing up a bit of fuel mist onto my firewall (the engine is in my FWD Datsun Cherry Estate) especially if the engine missed.
So I was wondering if any of you had tips for tuning up a pair of SU carbs for someone that has never tuned, or owned a car with SU Carbs before. Also if you have any tips about how I should adjust the timing, or anything else to get the most out of this setup I would really appreciate it!

Thanks!
Will