Originally posted by PHiZ
chipping is just another tool to tune, it helps if you can custom write chips like I can. But even so the ability to manipulate sensors, revlimits, vtec crossover, for the layman is nice.
O2 sensors measure the pressure of oxygen in the exhaust gas, ****ing get over it: here
but even beyond all of that, an OBD1 system will eliminate the 2nd 02 sensor location behind his cat, which is causing problems (we think).
However, as it stands the AFC hack is a pretty decent way to tune for a turbo. The Honda ECU maps don't have the enough resolution (they cut out at a very low MAP, to make them less usefull for turbo tuning)
Now if someone was ingenius enough to code a rom that realized when you reached the end of the millibar table, and then jumped to a routine, that used a multiplier with the start of the fuel/ignition map, that would be quite a hack 
And your contradicting yourself, if the chip does not suite your purpose, you can tune around it with the AFC. However you will definitly benefit from the more agressive fuel curves.
Careful though, california people you have shitty gas, so you probably want to couple the turbo with colder/or less gapped plugs.
(see 1stgencrxer, I'm trying to be more mindful of peoples locations)
And WHO exactly spends most of their time in open-loop operation??? Unless you race everywhere, you probably spend quite a bit of time at partial throttles...
OH, and the GSR ecu is fine, it'll run P28 roms, no problemo, and if you got it for a good price, congrats, check out what the P72 goes for on ebay, might be worth your while to sell it and grab a P28, plenty of off the shelf chips available for that one.
-PHiZ
Are you familiar with
Dalton's Law? "The total pressure of a gas mixture equals the sum of the partial pressures that make up the mixture." Partial pressures refer to the proportion of one gas in relation to the entire mixture of multiple gasses. You cannot measure partial pressure, you calculate it based on the volumes of each gas present in an enclosed space. The voltage created by the oxygen sensor represents the amount of oxygen present in the exhaust tract which is used to calculate the partial pressure of oxygen, but it does not measure pressure.
The OBD2 system is not the cause of the problem--if it was then it would have showed up right away when the turbo was installed instead of months down the line. The oxygen sensor is bad and needs to be dealt with but for some reason every time someone mentions that their oxygen bad you assume that it's time to backdate to OBD1. Shop manuals have troubleshooting procedures for this sort of thing you know.
OBD1 and OBD2 ECUs deal with oxygen sensor data in essentially identical manners. Getting rid of one of the sensors and switching the ECU is an unnecessary expense and doesn't solve the root issue of the problem which is not the ECU but the oxygen sensor.