How to set PRP for MAFia and also up fuel pressure

MalcolmV8

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Hey Guys,

So my prior build was almost maxing out my MAF. Counts were in the low to mid 900s and car dyno'd 705 whp. I've since bumped CR with flat tops, ported the heads, added cams and long tubes etc.
Still breaking in the motor and getting things going but pretty sure this MAF curve is going to peg so I was going to install my MAFia on setting #2.

For the record it's a stock 07-10 GT500 slot sensor in a 5.1" housing. I googled the doc from Diablo and it says do this:
"Using the settings chart, reduce the following parameters in your software by the correction factor.
Fuel Injector Low Slope
Fuel Injector High Slope
Air Mass Displacement of one cylinder

#2 24% or multiply by .76"

So that's kind of interesting. I thought for sure what I'd need to adjust is the MAF transfer curve? I'm using SCT PRP to tune the car. Can someone explain the theory behind that to me. Trying to wrap my head around what I'd be doing there.

2nd part of this equation now is the ID1000s. I'm afraid I'll be maxing them out too with E85 and the current build. What's involved in bumping the base fuel pressure up? Can I just adjust my regulator (I have a return fuel system) and then adjust "pressure drop across injector" in PRP or is there more to it? Still using search but seem to find conflicting results.
One thread said just import the value file. I'd prefer to know what I'm doing and why.
One thread says you don't need to adjust the fuel slopes unless you have the fuel rail pressure sensor deleted on the return system. Another said the opposite. I do have the sensor if it matters.
How does adjusting the fuel slopes for the MAF and then adjusting them again for the fuel pressure work? Seems like a conflict.

Thanks
Malcolm
 

decipha

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simple just calc the actual injector values for the injectors you have at the pressure your running

then calc the actual maf curve for the maf and diablo multiplier

divide the max maf flow by 1500 kghr and come up with your scaling percentage, then apply that to your injector slopes and breakpoint

its covered in the scaling write up

http://info.efidynotuning.com/scaling.htm

if your scaling percentage is greater than 5 which im sure it will be i have a rough approximation to get it closer for fire off, just let me know and ill help you out

Is this for the marauder with rzasa ? If so, i have the rzasa def file done for tunerpro, i made some changes to the adx a few days ago and screwed up the logging so i gotta fix it before it can log again with the quarterhorse but the def file is 100%, you can still log with the xcal and realtime tune with tunerpro
 
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MalcolmV8

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Thanks I'll read through the scaling write up before I ask more questions.

This is for my 03 Cobra. I'm using SCT FBGI0. I was attempting TunerPro with the Quarter Horse using FBFG2 with AMZ3 but it throws a check engine light due to VSS circuit failure (which is false) and as such locks out my reverse solenoid so I can't get the car in reverse. It also doesn't log IAT1/2 but instead displays a constant value of 60. Till I can figure those out I'm back on SCT PRP.
 

decipha

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the vss and reverse lock out are unrelated, the reverse lockout isn't enabled in there, i can very easily add it in though when i get some free time

imma have to take a look into iat2 as it seems to log fine for me
 

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