Hey.
From what I understand, the stock SMIC is insufficient to support anything but the stock 14b (I still haven't upgraded my turbo, this is all hearsay). I took the intercooler off my last car to compare with the front mount on my brother's MkIII Supra, and its fair to say it was dwarfed. I talked to a performance vendor at the Chicago auto show about a new intercooler, and he said if you're looking for performance you might as well go all out and buy a spearco/greddy/big ass intercooler...if you get a smaller stock unit off another car (i.e., a Starion) it'll be better than your factory sidemount, but still not capable of supporting max boost (I was asking him about a 20g, maybe its good enough for a 16g). Hope I helped.
Chris