yes but what is the psi at the freewway RPM/VAC when it is surging? And it was fine with the prior carb, & it was a freeway cruise (not exactly a WOT demand). I'd still say it's a carb issue (lean) or psi issue right at the carb (filter/orifice) that's restricting flow/making it lean if the carb internals needle/seat/floats etc are letting it flow enough which wouldn't normally be a problem unless some system is acting up inside the carb