When the car was setup after the top end rebuild and the carb was re jetted the afr has been reading 11.9 on idle, with the mixture screw out as far as it would go. Over the last two weeks it's been steadily rising up till now 13.2. At about 3k foot down my afr is rising to 17 and when on boost 3.5-4k it settles down to 15. As fa as afr tuning goes I have hardly any experience
What would cause the afr to creep up? Is it time to get a updated fuel pump?