We're busy dialing in a LSJ + TVS (3.15 pulley, 60lb's, ported head with springs. balance delete, 3" MAF tube) AFR's are pretty spot on, but in the log it's sometimes commanding a 13.9 AFR during cruise. This often happens after a pull and Fuel Trims stop at those moments, but my Closed Loop flag shows enabled...
Any clues what's causing this? (Read something about AC causing a 13.9AFR, but this car has no AC fitted.)
Also we have some idle issues. TB is clean and after tweaking it's now OK-ish, but the STFT's show very little up-down movement. Is this typical for 60lb's? My own 42lb tune shows a clear saw-tooth pattern at closed loop idle.