openecu.org

Does anyone knows if it's possible to do with ecuflash? Car is 2004 USDM WRX. I want to have one file for pump gas, another one for NO2 or aquamist water methanol 50/50.
Here is the original ROM.

I can develop it if needed.

Try the CarBerry speed-density ROM. It'll require some serious re-tuning being an SD map but does support what you want.