First -- did you set the fuel pressure with the vacuum hose attached or disconnected and plugged? Stock fuel pressure spec is 44 psi (3 bar) with the hose disconnected and 36 with the hose connected, both measured at idle. So, if I'm remembering everything correctly, then I'd suggest that you should have set the fuel pressure at 59 (4 bar) with the vacuum hose to the FPR disconnected and plugged. If you set it with the hose connected, the pressure may be too high. Either way -- it makes a difference, and you need to get this correct. On my NA SR20, changing the fuel pressure 3 psi moves the AFR half a point (e.g., 13.0 to 13.5).
Once you confirm the proper fuel pressure, you can start making changes to the tune. If I read your post correctly, you are now getting 10.1-10.3 AFR at WOT. If this is not what you want, what AFR are you targetting? If you need to lean it out, I would start by changing the K value. This will lean out the whole fuel map, just the opposite of richening the whole map by increasing fuel pressure. I can help you calculate a new K value if you need help dealing with hex and that kind of thing. Just tell me what AFR you have now and what you want it to be after the change. I can get you in the ball park. But to do this, you will need a ROM editor and a chip burner.
I'm not an expert, especially with turbo, but I am willing to help out. Let me know.
Bill
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