Wondering if anyone can help, I have a quikfuel 850(no choke) on a 434 sbc in a 66 nova, m22, my current problem is after a couple wot runs around the block the car starts to run terrible around 1/8 throttle(major hesitation). Upon inspecting the carb the primary side is always covered in black residue, which I believe keeps clogging my air bleeds, which I believe is what causes it to run rough, after I clean it down with carb clean it runs good again, so I'm wondering what is causing this to happen. I'm new to the site and learning as I go, so any words of wisdom would be appreciated, thanks.