How lean can I go?

[dirt_track_racer_81]

on my 5.3 truck I have a custom os and speed density tune.. in my commanded fuel vs rpm table i have my A/F at cruising speeds set to 15.8..how much leaner can i go before i run into some problems??? how lean can i go in just city driving speeds??if i go to change these numbers around do i need to stick this back on the dyno and auto ve tune this again?

[Redline Motorsports]

Anymore then that and it will start to lean miss. Especially if you get some bad gas!

I guess you can continue to lean it out and see when you hit bottom. If its at part throttle light loads you can get away with a leaner mixture. Make sure PE mode is at least no leaner then 12.9!

[ringram]

You can likely lean out idle a little more. Try with the bidirectional controls to make sure it runs nice and lean it out until you notice it getting rough. Richen it up a tiny bit, then play with timing until you get min map vac. Update the tune and you will have a nice lean idle. From there you need to enrichen progressively towards WOT. You can also use DFCO aggressively and perhaps lean up even more map points below your idle map.

Hey over here where petrol runs $6 a gallon I do all I can to get economy. Cruising I keep under 16:1 as it gets a little rough otherwise. Stock cam was fine leaner, new cam doesnt like it as lean.

Looking at some lean best burn tables there isnt much to be gained after about 16:1