Recommended CO level/range for 2.7 RS Engine?
What is the recommended CO setting for a 2.7 RS spec engine with MFI? Mine is measuring 3.5% @ approximately 2500 rpm and 2.25% at idle. At these settings I'm getting some slight surging between 2000 rpm and 3200 rpm. I'm thinking I should adjust the part throttle fuel mixture setting on the MFI pump to richen the mixture more, but I have a CO meter, so thought I'd ask the experts what level I should set it at? Otherwise I guess I'll just keep adjusting it richer one click at a time until the surging goes away.