And wire your wastegate open so you're not getting into boost (and richer AFRs)

without knowing where on your map the dyno run will fall, it's kind of a crap shoot.

You might want to just make a copy of your current map to change to a "no boost, pass emissions ONLY" map.

The Hydra-powered engine does have the ability to produce clean tailpipe emissions when it's properly calibrated. The fact that Hydra-powered cars generally get as good or better gas mileage than stock cars underscores this. The basis of this is that first you must have your base fuel table dialed in as close as you can so that any day-to-day variances in fuelling can easily be trimmed out by the closed loop O2 sensor system. Beyond that, here are some hints to improve your engine's emissions. Start by saving your working map before making all these changes for your emissions map so that you can revert easily after the test. A) The factory NBO2 sensor is better at regulating stoichiometric emissions than the WBO2 sensor is. Switch the Hydra control back to the left narrowband sensor under Settings -> AFR target settings -> Left module sensor source (assuming you still have the NBO2 sensor installed). Make sure the left module closed loop & long term trim are both enabled. B) In your AFR target table, assuming you are doing this for tailpipe testing & not for normal driving, set your target to 14.7 across the board. This will ensure that no matter what the worker at the test station does with his right foot the computer will be trying to trim it for stoichiometric. C) Set your throttle pump fuel trim table, throttle tip-in fuel trim table, post-start fuel trim decay & your post-decel cut fuel trim tables to 0 across the board. This will prevent the worker's digital right foot from throwing rich spikes into the test. Also drop your Closed Loop Start Delay table to 0. D) Drop your base idle speed target down to the target RPM on the emissions sticker under your hood. E) Drop your maximum boost down to around say 4 PSI / 128 kPa so that the ECU won't let the engine go into boost. F) Turn off air conditioning (including defrost on 2001-05 cars) and other electrical loads. G) Zero out your post start idle speed target trim, post start fuel trim, post start throttle pump fuel trim & (closed loop) start delay maps to keep it from being rich when the operator runs the test immediately after stalling your engine & restarting it. H) Make sure the car will still hot restart smoothly after doing all of these things. I) Set your fan temperatures hotter so that the engine runs hot, say 105°C / 221°F. J) If you have a well-developed LTT table you should apply it back to your base fuel table, and zero out your LTT table. We have a spreadsheet available for doing this manually- email us if you need a copy.

Your maps should not be locked, you own them

you might need to change your "experience " level from Novice to Apprentice or even Expert. That unlocks some controls. Open your map and go to TOOLS > EXPERIENCE LEVEL > APPRENTICE.

It is unlikely that your car will pass with the Hydra installed, as the Hydra does not support EGR (nor am I aware of any other aftermarket MIata ECU that does).