Check this out for some fine tuning help
http://www.cjclub.co.il/files/Weber3236adjust.pdf
Probably doesn't hurt to bump the idle up by 200-300rpm to stop it from stalling. As for the backfiring the needle in the float might not be seating correctly and over fuelling at idle and if you are pushing the accelerator to clear it this will just push more fuel in and then the backfire happens. Once it is warm it would go away as the petrol can vapourise a little better. Just my thoughts on what it could be.
I don't know if there would be much difference in jet setting between a 2T and 3T unless it came off a worked 3T.
The beauty of the 32/36 is that they are reasonably easy to play with and pull apart so do some reading and have a crack yourself. My 32/36 was overfuelling at idle and would die in the middle of traffic and I kept pushing the accelerator to clear it but that just forced more fuel. The RACV guy said to push and hold the accelerator flat to the floor and that would open the butterflies but not force more fuel in so I could then restart it. Simple when you know how![]()
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