backfire/stalling

[alarot]

just bought another Model A and having learning curve issues compared to the one I used to have. This one starts and runs pretty good but was constantly stalling when I came to a stop. Decided to start with tune-up/ timing and plugs and now I have an occasional backfire as well when I let off gas and it still idles down to a stall.. Retime and try again or might it be carb issue as well? Any positive ideas would help!