I Finally got my car running. Having issues, when I'm driving the car makes a weird sound from the engine at 2000-2500 rpm underload. I'm getting decel pop and little backfiring. My fuel pressures at 3 psi, timing is at 28 degrees. I am running Weber 40 IDF dual carburetors with 50 idles, 200 air, 145 main jets. So I did some tests. I found when I cover #1 cylinder on the top of the carb it doesn't stall or slow down. I did a compression test and it is good. I did a leak down test and it was not leaking anywhere. I sprayed a little brake clean around the base of the intake near the cylinder head while it was running and I didn't notice any change. I sprayed the throttle shafts on the outside and didn't notice any change.I pulled the intake thinking it might be the gasket. It tore a little on the stud ends coming off so I couldn't tell if there was a problem there. I checked the base of the intake where it attaches to the head it is flat. My carbs are new but they were sitting for a long time. I did go through the carbs and check for dirt and corrosion and cleaned them. I noticed the top gasket is thin. When I disassembled the top of the carb it appeared the gasket had good compression marks like it was sealing.
Do I have a bad carb?