This is an update to my fouling plugs, misfire, primary throttle stumble, and rich idle.
One of you guys recommended trying with the secondary idle mixture screws closed all the way. I set them to 1/2 like a few of the guys did on the Chevelle site. I set the carb via highest vacuum with the primary mixture screws only. I ended up at 1.5 turns. That cleaned it up a lot. I mean a lot. Stumble remained. I learned that opening the secondaries anymore that 1/4 turn caused the stumble. I left them at 1/4 turn. In order to maintain my 900 rpm idle, I needed the primaries open 3/4 turn at .030 transition. It likes .020 better because it will stall if I close any of the 4 mixture screws, but idle would be too low. At .030 transition it will only stall if I close the front mixture screws. I can close both secondaries all the way and it will still run. It runs rough but runs. The secondaries still respond, just no stall. I left them at 1/2 turn anyway. This carb really likes this set up. AED said just because it doesn’t stall when closing mixture screws is not the whole picture. It runs cleaner now with no stumble.
i do have a small RPM dependable misfire. It started the second I installed these Autolite 3924’s. I’m switching to FR5’s soon pmug an oil change. Draining the 5w-30 Lucas break in oil for SAE 30 lucas breakin oil. I’m still.burning a little blue smoke at full temp under load.
have to wait though. I blew the radiator, so more delays.
also, call me crazy. I know this goes against the carburator gospel, but I swear that switching the primaries from 77 jets to 75 helped clean up my idle.
what do you guys think? Any issues with the above settings?