I have an edelbrock 1405 carb on my 355. I also added an electric choke. The idle is pretty good but when I am driving, say third gear and am just holding the gas at a steady, the car jerks violently. If I am on the throttle it runs fine, the moment I try to keep a consistent speed it goes into jerk mode. I should mention that I just installed a msd 6al and ended up messing with the mixture screws on the front of the carb while trying to get the optimal mixture. So I need to know what would be my next best move to get her back to running properly. Oh also there is an occasional backfire wile in the lower rpms. Thanks

on the dl

 

I think i have the same carb . sounds like your too lean for the idle mixture . I think the way to fix that was get the car warm , turn the idle screws to pretty much a close . then turn them each a little richer and you will notice the idle speed picks up . you make it rich untill the idle speed no longer speeds up , then you adjust the idle . if that doesnt work try swearing

 

Right on Mac, I will try it as you describe. Many thanks.



on the dl