Yes a fuel regulator, I had it at 3psi and turned it down to 1 psi. I replaced the old one with an aero regulator. It still did not reduce the richness of the engine.
I have completely going through the carbs and cleaned and replaced multiple things on recommendation of z therapy. I have a 280 that was carbed and it runs rich like can't sit in the garage for more than 10 min without hurting your eyes. I replaced the fuel system, just turned the fuel reg down to 1 and did not change it. I am going to try the idea you have in the picture, that should work. Thank you for the response.
Are you still selling the Float sync tool? I cant find it on ebay. I saw your video an think this may be my problem, I would like to test it.
Thank you