[Jared at Pelican Parts]

I think he is talking about upgrading to a larger AFM and larger injectors. It does give you a very slight increase in power, provided you tweak the CO mixture. (Not something you want to do unless you have a meter and want to pass smog) Gains on a stock motor would be maybe 1-3HP, if that.

I did it on my car to accomodate my headers, which gave me a slight flat spot in the upper RPM range. Car was running too lean due to the scavenging effect of the headers. A bigger AFM (off a 535i) and injectors (off a Mustang 5.0) fixed it.

Wayne is right, though, you really dont need to do unless you have turbos, larger displacement pistons, etc... In my case it was somewhat overkill.