I don’t know what you mean by running out of adjustment.  Do you mean that turning the mixture knob fully CC it’s still to rich?  If so; follow mode 1 instructions and program it much leaner.  However, I don’t think that’s the only issue.  I could get mine lean enough, but still not get smooth running at low power on those stock primary injectors.  I lowered the fuel pressure by 10 psi and found no noticeable improvement.

 

Yes,  Leaning in mode 1 as low as it will go, still results in a rich mixture.  I really don't have any issues with it running rich, it runs really smooth, even down to about 400 RPM's.  I'm just getting allot of carbon around the exhaust, and the A/F gauge has all but the last light lit.  If I run the fuel pressure up, all the lights are lit.  I don't get any controll over it until about 3000 rpm's.

 

 

It begs the question: What did Mazda do to get good idle on those big injectors that we are not doing?

 

I'm sure that Mazda's ECU works different than Tracy's.  It probably could shorten the pulse enough at low RPM's to keep the mixture in line.  I've adjusted the injector setting also, and it helped, but I really can't go any lower, because the high power mixture is starting to go lean.

 

I beleive that John Slade also has a rich mixture issue, but I'm not sure that it's only at low power.

 

 

Using the 440cc injectors may help; but I don’t think there is any assurance that they will work well.  Didn’t Rusty try this?

 

I don't remember it, but he may have.