Phil,

When you're adjusting the jets for the best idle, do you blow out the carbs after each adjustment of the jet(s), i.e. by giving it a blip of throttle? Or do you not touch the throttle and just move the jets?


To the original poster,

I would agree with the suggestion to try running at 12 flats. It's hard to imagine a functional SU running too poorly at that setting. Also make sure your PCV lines aren't leaking anywhere. Perhaps replace the hoses and add some zipties to the connections, to prevent small air leaks. If you've got a brake booster running off the same line as well, make sure it isn't leaking air either.