I was just wondering what a wideband o2 sensor is, and what is it used for

 

IIRC wide band refers to a type of dyno run. Using a wide band dyno will give you a/f ratio related to your dyno plot.

 

its highly accurate sensor to determine A/F ratio its not just for dyno runs...u can have one in ur car at all times to measure air/fuel ratio....makes tuning alot more precise

 

The big difference is in the sensor output.

A normal O2 sensor basically changes voltage the moment the car goes from rich to lean (stoich.). There is very little ability to "read" the true a/f ratio because it swings over so fast. It's only used by the ECU when the engine is under very light load (cruising) which is ok since it's safe to run near stoich in that situation. However, under medium or heavy load, the engine must run a little richer than stoich, and exactly how rich is very important for good tuning. A normal O2 sensor is useless for this since it pretty much says 'rich' the whole time.

A wideband produces a smoothly varying signal that will give accurate a/f ratio readings all the way from pig-rich (9:1) to lean. This 'band' of useful signal is comparatively 'wide'. If you're tuning this is the best measurement to base it on. Dynos and widebands go hand-in-hand as the most valuable in-shop tuning tools.

Dave

 

do they do any good just in place of a normal o2 sensor hooked up to your non tuned ecu

 

eh not really...they are kind of pointless if u dont have any kind of fuel tuning device such as a SAFC..........or E-manage...EU....u coudl get one to acturaely read ur fuel but on a stock ECU no need

 

I dont' think they would work with a stock ECU.