Injector Scaler

Jay Jr

Jay Jr

Pump Gas Sucks
Okay, quick question.

As quoted from SStock's '05 FAQ's
"If your startup A/F's are too rich you need to input a higher scalar value, and if too lean a lower scalar value."

Is this backwards or is it just me?:headscratch:
Wouldn't a higher scaler/ injector value equate to dumping more fuel?

I'm just starting to attempt to tuning on my new setup and may have several threads seeking quick tips.

Thanks,
Jay
 
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Its you. Do just as stated:D
Think about it in these terms, if you place a 42lb injector in the intake and remove the 19lber and not change the tune it will be pig rich on startup, to lean it you would need to change the scaler value in the tune to the larger scaler value to lean the combo.
Make sense?
 
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Okay so here's how I look at it. . . Example: If the scaler is set at 42 (.0117) and start up shows rich, then your tip says to input a higher scaler.

Said > 30lb you should intially try [(x)-4] to start. Yet, if 42 shows rich you suggest a higher scaler?
While, a 38 (.0106) wouldn't be a fix, it'd be richer yet?


Giddy - it runs yet haven't had the opportunity to drive/ tune or even check to see if caledit is going to cooperate. I have a SStock startup from a bit ago. Setup is a little different (Cam/ CFM blower). Truck is also 400 miles away so it's a bit stressful trying to gather my patience.
 
need to make sure your fuel pressure is close to stock settings or it is going to mess with your tune. i haven t had to run higher than 38/39lb scaler on ford 42s.


with that being said,yes if it is too rich,you make the scaler high than 42.
 
Okay. They're FMS 42's and if I recall (vac off) fuel was 37psi at the reg. Where should it be?
 
thats about right... did you get a log of start up air fuel? and remeber you have to let the wideband warm up for a few seconds before it starts to read.
 
No log. I don't have a tach signal. Yes, o2 takes a good twenty seconds to warm up engine off.
 
Jay Jr said:
Okay so here's how I look at it. . . Example: If the scaler is set at 42 (.0117) and start up shows rich, then your tip says to input a higher scaler.

Said > 30lb you should intially try [(x)-4] to start. Yet, if 42 shows rich you suggest a higher scaler?
While, a 38 (.0106) wouldn't be a fix, it'd be richer yet?
Click to expand...


No reread my first response
 
Think about it in terms that a given gas engine needs X amount of fuel to idle with regardless of the injector size, the fuel need is the same. A larger injector will need to have less of a pulsewidth than the cooresponding smaller injector to supply the same fuel amount. When you increase the injector scaler value in the tune, you are in essence fooling the computer into thinking it has a larger injector installed, which in the given situation will reduce the injector pulsewidth to deliver the required amount of fuel. Then end result will be a leaner mixture in open loop.
 
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