Thread: SR's Without o2 sensors

just seen the thread from rnd2k saying his motor runs without an o2 sensor. mine is the same and has no 02 sensor. how is the ecu finding out the mixture it needs?

Mass air flow sensor

Some early P10 GT came without O2 sensor and MAF sensor was different.

ah ok. i presume this means the ecu is different too?

I have both .bin files, they are almost same.

OBD1 or OBD2?

OBD2 doesn't work too well without an O2. OBD1 on the other hand does just fine. Calum actually disables the O2 sensor on his OBD1 tunes.

You have fuel and timing maps. ECU goes by them at all times. It's just when O2 sensor is present, it ignores the value in feedback cells.

My O2 sensor just get f***ked.

SR20ve with Calum basic.

Does that mean I DONT have to get back one in.

Havent driven the car since but I have a few appointments this weekend on the 1320.

Thanks.

Peace

He disables the o2? No wonder my car didn't seem any different when I forgot to plug it in....I'm running a turbo tune with 370's, 4 bar, 300zx maf b13

I'd really like mine to work. I know it's cycling, I remember hooking a consult 2 to it and watching it, I guess his tune just ignores it?

I haven't even messed with my real time since I got it, I have a crap load of free time, but not much cash, guess I have something to do tomorrow.

On both pictures, the two MAFs on the right side - this is how the MAF from a non o2 SR20 looks like. HITACHI 22680 59J00, AFH50-07 1
There is a round cap on the MAF. By removing it, you should see another small aluminium tap. Some people drill a hole in that small aluminium tap. The reason is the screw underneath. Turning that screw left or right lets you adjust your emissions, which I assume is more over like telling the ECU how rich/lean to go. But yes, this is all manual, no o2 readings, no nothing.
Here in Europe only B13, N14 and P10 were ever using that non o2 SR20. And if it comes to power - you simply have no idea how much powerful these engines are! They also came with no cats and EGRs.




On the below picture is a comparison between my AFR (64kb *.bin) vs. non o2 AFR. However, this comparison is not quite accurate since my *.bin uses VE table as well, which explains the crappy numbers. But you got the point - the second table is the non o2 one.

My mistake guys, I thought I saw him say it himself. I definitely heard another tuner tell me that Calum disabled the O2, but I guess that was for his specific setup.

Best bet is to double check your tune

http://www.sr20-forum.com/calumsult/14187-few-questions-regarding-vvl-bin.html