Excellent info Tone. I greatly appreciate it. I forgot that we're using a MAS to measure airflow...I'm used to speed density systems, no restrictions, better for hp, but you need to be a really good tuner to get things right. I'm surprised the ECU has enough cell "range" to cover 5psi. It's very good news though.

What is limiting us to 5psi? Is it the cast pistons/rods?

On the rich fuel settings, forget a Unichip. I have a local here in town that tunes Porsche's this way...seems way too expensive to me although you can modify timing. One electronic unit you may wish to try out is the Apexi S-AFC which is a $350 "box" with LED display that allows you to +/- air fuel by 30% in either direction. One would need to acquire a PIN out map for the stock ECU and as it's universal, it'll cover any car out there. You'll also have to know if TPS voltage rises or falls with throttle application. I used it and a LINK system (Flyin' Miata uses the LINK out of Australia) and had better drivability, ease of use with the S-AFC. Might be worth your while to try out.

There's also something called the Do It Yourself wideband which uses a Bosh and NTK UEGO sensor (wideband) to measure a/f ratios. Place a bung in your exhaust BEFORE the catalytic converter and you can monitor accurate a/f ratios. Cost is about $350 for the sensor and DIY "box".

I'm at work currently but I'll get links for everyone when I get home later tonight.

Thanks again for the info!