I swapped out my mercarb last year to the Holley 300 cfm 2300 marine carb. Has anyone tried using a wideband o2 sensor to tune their carb. So far my carb is extremely rich from idle to wide open. My idle was 10.0 and my midrange was 11.5 to 12.4 and wide open was back to 11.5. My boat ran fine I just felt it had room to get better and now I know why. I have a few smaller jet sizes on order as the little carb takes a smaller jet than what I have in my box. I am hoping be able to lean this carb out without having to order a totally adjustable metering plate but I doubt that I can get the off idle lean enough for my liking. I will post my progress as soon as I change the jets and test it out again.
