ive been trying to lean out my idle to save on gas. my car likes to idle at 12.0-12.5 afr. anything leaner and the idle likes to pulse up and down. the only thing i can think of is playing with the timing. i thought id ask first before i try, any ideas?

 

What kind of porting do you have? I managed to get mine to around 13.5:1. I have had it up to ~14:1 IIRC, but it's definitely not happy. Play with the timing a bit, it will help. Another little trick is to place the cells in the 500rpm map richer than those in the 1000rpm map. That way, if the idle drops down too low, it will get extra fuel, which will help raise it back up. The opposite also holds true - if it gets close to 1000rpm, it will lean out a bit and tend to drop the idle back further towards the 500rpm map range. Remember that between rpm points (500 1000 1500 ... etc) the Haltech uses linear interpolation (i.e. at 750rpm it uses the [500rpm map value + the 1000rpm map value] divided by 2).

Cheers,
Manolis

 

my motor is a streetported s5 engine. thanks for the info, you gave me some very interesting idea's.

 

and dont just tune the bar its on, it interpolates the bars next to the one its on.

its helpful to look at the text, and make sure its consistent in all those ranges.

ive found timing doesnt make a huge difference, but try it, ive heard about 5BTDC L is good