Hey guys
Just got back from the dyno and made 168 kw at the wheels. It had some detonation and I checked the widebands. My tech edge (2J) pre built wideband was reading 11.5 but the dyno (big dollar) wideband was saying 13.5.
Have I set my wideband up wrong? If anyone has this wb can you tell me if you used 0-5v linear etc.

my sensor is located before the cat

Cheers

 

Where was theirs? Exhaust-tip widebands tend to run leaner.

I discovered recently that exhaust pressure alters the reading as well. Where is yours?

The only way to truly know what your AFRs are, is to measure the air flow and measure the fuel flow. Widebands get you close but they are not necessarily precise.

 

There are a lot of things that can cause the wideband to read different from the dyno one. Some peejay covered.

Did you read the AFR from an AFR gauge connected directly to the wideband, or was it from megatune?

If it was from megatune, the cause is often that you had the wideband grounded to a different place than you had the MS grounded. If there's a voltage drop from the wideband's ground to the MS's ground, that will show up as the MS reading a different voltage, and therefore a different AFR. In my experience, usually the MS will show a little leaner than the gauge hooked to the wideband controller, but it could go the other way.

Other things can affect the accuracy of widebands, such as temperature (which is why they shouldn't really be trusted at full-throttle (NA) or on boost), pressure, calibration, etc...

Ken