Holley 2 barrel (350 cfm) on a 302- Adjustment advice

[BigOrsnge]

I seem to be getting close on my settings but can't quite get it dialed in. I've adjusted float to where I barely see a splash of gas in the side window on the carb (general setting for these). Reworked my choke so it's not hanging up my idle now (plus it's 96 degrees outside anyway). Adjusted fuel mixture (about 1.5 turns maybe slightly more). Adjust idle and accelerator settings. Idle is still a little off and it wants to run between 800 and 1200 RPM at hot idle right now. Getting a little bit of backfire through exhaust (usually means lean/timing?). Running long tube headers with dual exhaust and cherry bomb mufflers. Anybody got advice or can tell me what that hot RPM idle should be? I was thinking 800ish. I was flooding with a stuck float and choke idle before. As always, I'm learning as I go...
Almost forgot, fuel pressure is running at 4 psi with the Carter. Never used a vacuum gauge to tune a carb but will if someone can tell me how LOL...

 

[B RON CO]

Hi, the ignition system must be 100% before you adjust the carb, so assuming your distributor is all good, set the ignition timing first, because changing the timing changes the idle speed. Work on a warmed up engine. Set the timing. Set the idle with the screw on the throttle stop. Then slowly turn one of the mixture screws in until the engine stumbles, and back it out one full turn. Repeat with the other mixture screw. Reset the idle screw on the throttle stop if necessary. Redo the mixture screws. If you can't get good results, check for vacuum leaks, and make sure the jets, squirters, accelerator pump settings etc. are close to the original when the carb was built. Good luck

 

[Broncobowsher]

Guessing a stock engine, idle should be mid to upper 600s.
You might be fighting a vacuum leak.

 

[BigOrsnge]

I've tried to find vacuum leaks with the inexact science of carb spray and haven't found anything obvious. So much older stuff on it, it's kinda expected I guess. No leaks around the carb or on top of the engine though. Checked all the obvious spots I could. I'm thinking timing is off a little but my knowledge is obviously limited. Also think I'm a little off on the mixture. It runs, it's just not idling great and has the slight backfire.

 

[BigOrsnge]

I'm done with this carb! Now it's not getting fuel. Was running fine but engine suddenly died and now zero fuel in the carb. Plenty of fuel to it, none in it. #%^* a carb!! I've been running almost everyday to prevent issues but...another one. What's the best EFI for an original 302? Time to move on because I'm tired of not being able to drive it.

 

[B RON CO]

Hi, I would get an Edelbrock 1406. They usually run good right out of the box. I know guys like the Summit carbs. Good luck