Maf maxed, WOT Lean-Out !!!
Thread Starter
3rd Gear
Joined: Oct 2003
Posts: 3
Likes: 0
From: St.Petersburg FL
Maf maxed, WOT Lean-Out !!!
I've got a 383 mini-ram, 245 deg 580 lift, 30lb inj, runing 6E w/guted maf that hits the 255 wall by 5k. O2 drops out by 5300, added fuel to PE, scaled back Maf vs RPM to not max till 6400 but still can't get enough fuel, rail press holds at 47psi. Comand fuel is like 10:1, time for some 42lb injectors or time for SD aka 730?
Melting Slicks
Joined: Aug 2003
Posts: 3,394
Likes: 393
From: Lakeville MI
Sounds like the time for bigger injectors (or more fuel pressure) 63 psi should make those 30s flow like 36s.
I'd be tempted to try this first.
42s may be overkill for an N/A engine. I just installed some 42.5 lb. Lucas injectors, but unfortunately I tore an o-ring on the fuel rail, so its not up and running yet.
I hope I can get it to idle well with the 42.5s. I know some have had problems at idle with 42s and the inevitable low injector pulse widths.
I would also raise the max MAF vs. rpm table so that you max the MAF earlier rather than later and add all the extra fuel via PE after the MAF is maxed.
Reducing the max MAF vs. rpm table in a attempt to extend the rpm range of the MAF is only making things leaner than necessary requiring even more PE enrichment.
Thread Starter
3rd Gear
Joined: Oct 2003
Posts: 3
Likes: 0
From: St.Petersburg FL
I know the 42's many be pushing it a tad, I was thinking about playing aorund with the pw adder around the idle, to handle the short pw
I did play with the maf max flow vs rpm and it did lean it out (scaled it back so it wouldn't see 255 till 6400) when I brought it in sooner I lost fuel control pig rich lower rpm with same lean out upper. I keep pushing the PE vs RPM up but couldn't keep the O2 from crashing out even though the conmand was like 10:1
I did play with the maf max flow vs rpm and it did lean it out (scaled it back so it wouldn't see 255 till 6400) when I brought it in sooner I lost fuel control pig rich lower rpm with same lean out upper. I keep pushing the PE vs RPM up but couldn't keep the O2 from crashing out even though the conmand was like 10:1
