O2 delete on a high hp engine?

[R32GT-R]

Is their any reason not to delete the factory O2's in an engine that will be highly tuned race motor. Ie. big turbos and 280 deg pro cams.

[xcye]

No reason if you are running AM ECU with WB O2.

[Smilez]

your signature says you have a PowerFC, just turn off the O2 sensors in the hand control. ETC-->Function Select-->O2 F/B Control

[Skym]

From what I understand, stock narrowband o2 sensor is designed to work with stock cams, good fuel economy at idle, cruise and is ignored by ECU when foot is to the floor (fuel map only). Once you upgrade cams, have to run engine richer (how rich depends on specs of cams / how much air they let into cylinders) and stock narrowband becomes useless (turn it off). Also fuel economy goes out the window due to running engine richer.

[R32GT-R]

cool, dunt it, just put plugs in the holes

[RSTuning]

I would leave the O2 sensor functioning,

They only work under part throttle to attain 14.7 afr. under wot you are open loop anyways so the 02 sensors are not trimming fuel.

Unless you want poor fuel economy ofcourse.

[Dragon Humper]

Bah, hogwash.....I can average 20mpg with my car and I have no O2s. No black crap all over the bumper either, it's all in the tune.

The only reason you will run richer with bigger cams is if you have a lot of overlap. Not that you actually are fueling more but that there is more raw fuel getting into the exhaust and making it richer, then the computer will pull back on the fuel a little and voila, you now have a lean stumble at idle. That's nothing a tweeking can't handle though.

The only reason mine had the O2s removed was because of the steady diet of leaded race fuel. Now that there is no lead here in North America I don't have to worry. I will be putting them back in next year to try to go for 25mpg average.


Jon.

[R32GT-R]

who is a good tuner in this part of BC?

[Zacho]

I would leave the O2 sensor functioning,

They only work under part throttle to attain 14.7 afr. under wot you are open loop anyways so the 02 sensors are not trimming fuel.

Unless you want poor fuel economy ofcourse.

If you have a good ECU and programmable wideband you can set the narrow and wide band inputs and outputs up so that you can use one sensor to do both. But even then narrowband is useless. Widebands can be used on many ecus as closed loop references.

[Skym]

Tomei mention how rich you run it at idle for different spec cams (stock, 260 duration, 270 duration, etc) -

http://www.tomei-p.co.jp/_2003web-catalogue/e140-157_reytec_page/e154-157_te-info.html

With 280 degree cams I gather it would be fairly rich at idle, probably into low 12's at idle and idle rpm would be alot higher (1300rpm?) to stop engine from stalling with those cams due to I gather vacuum being so low at idle with more aggressive cams, stock idle rpm. Of course cam gear adjustments (overlap, etc) probably would affect idle.

From what I understand, stock ECU uses what's inputted on fuelmap as the target A/F ratio (around 14.7:1) and o2 sensor lean, rich trigger voltages (converted to A/F ratio, so know where to adjust them to) are adjusted to be leaner or richer than what's inputted on fuelmap.