hey guys,
i need your help and recommendation again. e36 board isn't too helpful right now.

http://forums.bimmerforums.com/forum/showthread.php?s=&threadid=179527

i'm thinking of just welding a bung and re-dyno.

thanks!

Yes, that's what happens when you unplug your O2 sensor. You need to weld another bung BEFORE catalyctic converter (that is if you have it).

See my response in your original thread......your car is behaving properly. That AFR curve is NOT due to unplugging the O2 sensor.

I just talked tp someonewho said that the way you car is running, rich and all is the way that your JimC chip is set up real concervative!

thanks guys,
so do you think i should try to get a custom chip that would lean the top end a bit. seems to be rich a little too much. i have heard that the ratio should be around 13.8 to 13.0 for best results. a ratio of 12 just seems a little exessive for an n/a car.

In my opinion I think you might want to shoot somewhere around 13.3:1 no richer than that.

But then again Im no expert. :)

If you were forced induced then I would say low 12 are good.

Originally posted by NickG
See my response in your original thread......your car is behaving properly. That AFR curve is NOT due to unplugging the O2 sensor.

Nick,

Curious as to how this would be, since most default programming pulls timing and richens the mixture in absence of a valid signal from the O2 sensor. Just kinda confused as to how it wouldn't effect the readings.

James

Wot bypass the oxygen sensor and uses map from the dme. :)

true, but I thought that was applicable only when it had a 'good' signal, and defaulted to a 'safe' map when no signal could be found?

The OBD1 DME doesn't have a default map in the absence of the O2 signal. It just runs right off the 'main' (and only) maps w/o any correction.

BTW, leaning out the mixture *might* get you some more hp, but I wouldn't bet on it. Remember, all you really have installed is a Euro HFM setup and a track-pipe.

225rwhp is right where a Euro HFM setup typically dynos at. And there's lots of debate as to whether or not the track pipe actually gains any power. Thus, I'd say your setup is running just fine.

Nick a question is the power gain on a na car from a larger HFM just better air flow less restriction as a stock one can support a blown motor up to a certain boost.

More than what a na can draw through??

Originally posted by NickG
The OBD1 DME doesn't have a default map in the absence of the O2 signal. It just runs right off the 'main' (and only) maps w/o any correction.

no kidding? didn't know that about the OBD1 setup. learned something new.

thanks for the info everyone!