Yeah, there isn't really much to do (compared to some other motors). More a matter of doing it right. Spot on regarding the turbo. Here's a few of my past dyno graphs (I've posted them before but it's probably fallen into the archived abyss). All on PULP 98RON. Can't really give you a true before & after on the intake manifold, as I changed turbo @ the same time too. Mine was more designed towards providing an even flow & mild power gain (so I didn't sacrifice). Power gain would vary by design of course (runner length/size etc). I'm still using the standard t/b & the ECU is still where Toyota intended. Didn't need to change throttle cable (stocker was long enough).
2L (with forged pistons, 8.5:1 C/R, standard intake manifold), Blitz K1380V @ 18psi top end (midrange spike/scramble), HKS 272's, HKS IC, Power FC:
About as far as you can go with your current turbo. No sacrifice @ all over standard (same downlow, significantly more midrange & top end)
2.2L (8.8:1 C/R, Pauter rods, custom intake manifold), Garrett GT3037 0.7 A/R @ 20psi, HKS 272's, Full Race A2A IC, Power FC:
Surprisingly still quite responsive dow low & off boost, much better midrange & top end
2.2L (8.8:1 C/R, Pauter rods, custom intake manifold), Garrett GT35R 0.82 A/R @ 20psi, HKS 272's, Full Race A2A IC, Power FC:
Not as responsive down low (still acceptable) especially off boost, better midrange & extremely good top end
I've currently improved on that by going W2A IC & an MSD 6AL (with blaster 3 coil). Same boost/ignition timing etc, & she's doing back to back 320-330rwkw (never heatsoaked on me yet). I recently moved house, so the dynographs have gone astray (prolly in a box somewhere), but it pretty much looks like the 312 run.
Happy snaps:
