Proform 850 dialing it in closer

I was talking with a guy I had done some heads for and supplied a cam to at the track one day.
He had been messing with his newly acquired LM-1....... dialing the numbers in..... to where he was really liking what he saw.

The main issue he was having was...... the car kept getting slower and slower.

I told him to just take it out of the car and tune for performance.
Then, put it back in to see where you’re at...... after you have it going good.
Car went quickest with the O2 reading high 11’s/low 12’s......... not the mid-hi 13’s he was shooting for.