We have developed a replacement NTK oxygen sensor with custom calibration. Each one is individually calibrated and then live tested to your Lambda requirement.
Wire length on this sensor is 16" so be sure you have enough slack in your main harness to reach. The OEM Holley sensor has extensions added and comes in at 24".
Suggested target Lambda to order for most common applications, again this is where we live test them, your sensor will be calibrated and accurate through the full range regardless of the Lambda you choose.
Boosted methanol use .5 - .6
Boosted E85 .6 - .7
Boosted gas .8 - .9
NA gas .9 - 1.0