Help with DFI gen7 and nitrous .

[JuicedXtreme]

Sup people , i'm new in this board .
I have an '99 Xtreme with an build 4.3L and it is running already with 150 wet shot from NX . But now i put an TNT dry shot so i could put a 2 stage setup but i don't understand what to do on the DFI . I have everything wired up on the DFI for the nitrous i just need to know where should i change so it can add the extra fuel when the nitrous kicks in . I have heard from some to add the extra fuel from the fuel trim in the nitrous configuration and others say to just put the number of orifice and diameter of orifice and the nitrous line presure and put the BSFC to .500 and the computer should add the extra fuel without going into the fuel trim . I'm confused now . I want to run like 100-125 shot dry and add an extra 100 shot wet for second stage and let the DFI activate both for an total of 200-225 shot . But i don't want extra fuel when the wet shot activate , should i just leave everything to 0 ( in the orifice diameter etc) in the second stage nitrous configuration ?
thanx

 

[aDFIguy]

DFI NOS works like this:

1.) Stage 1 Active
2.) Stage 2 Active
3.) Stage 1+2 BOTH Active

The ECM will automatically add fuel to compensate for the nitrous flow indicated by the num orifices/orifice size/BSFC fields on the NOS config screen(s). You can modify this fuel value by using the Fuel Trim screen, and change your timing by using the Ignition Trim screen.

If you don't want extra fuel added when a given nitrous stage is activated, leave the orifice size set to 0, and make sure that your trim value for that stage is 0.

Here's how I'd do it:

Stage 1: 125# Dry Shot (Only)
Set your number of orifices and orifice sizes accordingly.
Set the Ignition Retard to come in as needed per your nitrous enable parameters.

Stage 2: 100# Wet Shot (Only)
Set number of Orifices to 0.
Set Ignition Retard as needed.

Stage 3: (Stages 1+2 at same time)
Orifice settings from Stage 1 and Stage 2 are used.
Set Ignition Retard to value for Stage 1 + value for Stage 2.

Wire the enable switches up independently, and you will be able to activate each stage independently, or both at once, just by pressing buttons. If you don't want the wet shot by itself, just leave the SOFTWARE enable for stage 2 off, and you can go directly from stage 1 to stage 3.

 

[JuicedXtreme]

Thank you very much . Thats exacly what i needed to know . I have everything wired exacly like you said too . So if i want i could leave the orifice size to 0 on the 1st stage and add the extra fuel in the fuel trim , doesn't it do the same thing ?
thanx again man.

 

[aDFIguy]

Both ways will work.

 

[JuicedXtreme]

Thanx