[Flathead Fever]

I agree with A bones, try running it without the air filters and see what it does. I have a 324 olds engine in the '28 Mitchel Muffler Pickup. About 25-years ago when I rebuilt the engine. I adjusted the idle air fuel with the air cleaners off. When I sat the air cleaners on the carbs the idle dropped. I thought that was strange at just idle. They were two of those small flathead 97 style air filters I had laving here. I swapped them out to a different design and then then the engine could breathe. Pretty bad when air cleaners won't even flow enough air at idle. That might not be your problem, but it will be easy to check. Also, make sure the throttle valves are opening up all the way. I have not done it yet but I'm going to start installing air fuel ratio gauges on my cars when I build them, that's if I recover from the stroke I had. I used the ones on the smog machine at work to check the engine readings on the dyno, but I was never allowed to bring my personal vehicles into the phone company's garage, too many eyeballs watching us in the garage. It would be really cool to monitor the fuel ratio driving down the road to get everything dialed in. There's lots of videos on those gauges.