Let me clarify the above statement - disregard the first suggestion, and follow the second...
The AFM on the R30 is useless, and has a sawtooth resistance curve. Not only that, it's got a rectangular mounting face which is a PITA.
If you must use an AFM, retro fit an SR or RB one (of course this would be if you fit an ECU with an AFM input).
Seriously, don't bother with the factory EFI if you're running a turbo conversion, it's just not worth the hassle.