just converted my tbi to carb i used i holley street avenger 670 cfm, i have the choke set, the idle mixture screw set, and the primary float level set. the problem i am having is if i rev the engine in park around 1200-1500 and up it will go super lean, my wideband tuner is reading an afr of 19 sometimes. what do i need to adjust to fix this, it has a horrible off idle stumble in drive as well, then it catches itself and drives fine?

what's your vacuum at cruise and what power valve are you running? now for off idle are you talking pulling up to a stop sign then barely giving it gas and it'll stumble for 2-3 seconds then catch itself?

not sure what my vacuum was a cruise i know it idles at about 60-65kpa, im running the stock power valve that came with the carb, and yes it i come to a stop at a stop sign and then go it will stumble and almost die, then i let off the gas and it will catch itself. every time it stumbles it goes lean.
----------
and it said it comes with a fourth gen power valve

accelerator pump?

Definatly sounds like it does not have enough acceleration enrichment.