ca18 bluebird, Is there a reason why you are running such short runners with that turbo manifold? You are loosing all the power gain from the resonance of the tuned runner length. You are letting the pressure wave from the intake valve closing leave the intake runner. this will cause a very poor cylinder fill when in the large cam lobe. A forced induction and N/A motor both use the same Tuned length resonance to help cylinder fill and take advantage of overlap scavenging. This does not change with boost. You may possibly gain overall flow by loosing the runner length because of the manifold design and thus will help cylinder fill, but you are actually loosing power and most likely spool in the midrange. I see a lot of Turbo people, Honda, Nissan, toyota do the cut-off, short runner intake manifolds because they think they are making a huge gain in power, but in reality they are only gaining top end power and actually loosing more everywhere else. I'm not sure how fast you are building boost but a GT30R .63 housing on a properly setup engine should make 1bar boost and 300lb ft TQ by 4000-4200rpm no problem. I have seen a lot of setups ( all makes here) with a .63 GT30R spool very late, closer to 5000rpm or later because of parts on their motor that they "think" is making more power but it is not. Many people just bolt parts onto their motor thinking its the best setup.
the 3 highest HP DET/VET setups I have seen all used factory Intake manifolds. Ported, reworked or indifferent, these motors all made 600+whp and 450+tq at "low" boost levels. 2 of these motors actually made more power than similar K/B series honda setups with similar parts, same turbo and displacement.
SERacer, are you asking about the ignition timing? or do you want more info in general on that subject? I can tell you that a few of the 2.0L motors with the correct cam timing and header design use about 24-25 deg advance at 8000rpm and these motors can generally be ran on 87 octane with no changes, except a loss in power, but no detonation. These make about 156-158tq at the wheels