If I remember correctly the SM-ARF doesn't require free air calibration like LC-1,2.

 

Read the install instructions, you need to input type of fuel, afr sweep range and like said you need to calibrate sensor out of bung by turning it on for 5-10 sec, then install it and go do a low gear run in truck to rpm limit and lift completely off gas for about 5 secs. do it 2 or 3 times. this will finish calibration for rich side.

 

I got no instructions with mine that say anything like that. I will check there website and see what i can find. Thanks