[Rod]

The choke riser tube and choke modulator are missing on my 57 set-up. Where can I get these items? how do they mount to the middle carb? on its base?

[pfilean]

I'm going to do a little guessing here because I may not be familiar enough with the 57 setup. But genereally back then the hot air tube entered the center of the choke stat. And I think that on Pontiac the tube would come from the heat crossover in the intake manifold (as opposed to Chevy where it came from the exhaust manifold). There should be a tube running from underneath the heat riser (getting fresh air from underside of the intake manifold) and coming to the top side just beside the center carb. The tube to the choke stat would then slip snuggly into that tube and go to the choke stat.
Parts could be hard to find for a 57 but try PY or maybe Ames Performance. The choke stat could be available from some of those who specialize in old Rochester carbs or find a parts carb on ebay and then get a new stat.
But then after thinking about it here's a picture that is supposed to be off a 58. May be the same as 57 - I don't know.

[carbking]

A picture is worth how many words?

http://www.thecarburetorshop.com/195...gerside3x2.jpg

Jon.