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I am sure there were some pretty advanced systems around but I am really generalizing with my descriptions. When I talk about OBD1 systems I am talking about the older computers that normally didn't have the cpu power or memory to handle long term fuel trims. Some did but most didn't.
I am also not going to get into the exact inner workings of an O2 sensor. suffice to say it measures lambda and leave it at that. I know how it works and anyone who cares to look can figure it out. When I said it tries to change the ratio from 14.7 to something else that is accurate. It doesn't 'know' what 14.7 is nor does it care. I have no interest in typing so much crap here that I accurately describe every test case and am just generalizing with the gm obd1 $0D system I have sitting in my driveway and also the megasquirt in my Metro. if you want to wander off on some rare exotic injection and test it then by all means test it out and give us some actual numbers. The GM and similar type TBI systems are really not that complicated. Trying to prove I am wrong by picking one random technical point and saying it isn't accurate isn't a good way to disprove the entire idea.
I have more diagnostic equipment than most people and have access to some pretty exotic stuff so I usually have numbers to back up what I say. All the testing I have done on my van was accurately measured and datalogged so I feel confident in my numbers. The only thing I don't have is an exhaust gas analyzer and steady state dyno but I will probably build one eventually to fine tune my metro a bit more than is possible with just a wideband and egt. The van is done being tuned and this weekend I will begin the diesel conversion project on it probably and actually swap it out in the next few months.
If anyone wants to learn how to fiddle with the gm obd1 systems grab tunerpro rt 5 beta. It is free to use and a few bin files and look at what information the computer uses. My exact setup is the 0D 1.75 advanced from moates.net and the corresponding ads file. My van's bin is BJLA but the BJLF is the 8 cyl version of the same bin and is also available on moates.net
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