What would cause maf #, air load, engine brake torque to datalog low values

[Thatwhite5.0]

This is on a 2007 4.6 with a roots 3.0L blower, 5 speed, stock tb, 100mm maf housing, stock cats, and bap. The car was previously tuned 370whp. I recorded a datalog and what I seen, I couldnt adjust anything to get air load where it should be.
Max MAF # was 19.
Max air load was .5
Engine brake torque was at 120ft wot with scheduled more than 500 ft lbs.
The air load is really messing up a lot of tables. I was thinking the maf housing, never had a datalog do this.
I can post a log and a the file I pulled once I get my laptop. I was thinking something mechanical. Not sure though.

[MRRPMBRP]

Seems like at one time, someone made a voltage lowering device to trick the maf to see lower air flow values, maybe make sure the car doesn't have one of these first?

[Thatwhite5.0]

Seems like at one time, someone made a voltage lowering device to trick the maf to see lower air flow values, maybe make sure the car doesn't have one of these first?

Man, it came close. The maf sensor had the iat wires cut right at the connector. The wires coming from the pcm were still routed towards the sensor but went to the back of the supercharger on the passenger side. It looks like someone got rid of iat using the maf sensor and added one the intake. I cut the non oem wires and hooked it back to the maf sensor. Got too excited because the pids I mentioned were still very low.
It idles at <.05 load and -20 engine brake torque. Even if I rev up a little. Engine brake torque still stays negative. I still think it's something mechanical. The iat temp sensor that was added looks home made with a piece of brass and a bottle cap.
I couldnt get it out with what I had with me. I wonder if its legit. The vacuum line for the boost gauge is pretty long under the hood with few Ts.
I have pictures of some of this but cant upload from my phone.
The line that runs to the gauge actually begins at the front driver side, the front of the fuel rail and front of supercharger are T'd together and a 2 foot hise runs under the manifold runner and qnother T with the gauge on the pillar and he boost device with the two male and a line to it. I have pics, log and tune once get my laptop

I noticed the throttle body is on upside down too. It doesnt fit right side up because they doesn't have the cmrc spacer so the supercharger sits lower than it should.

[B E N]

Posting a log would help, air load seems low, your MAF charge seems low, I get around 42 lbs.
How does it drive?
My whipple charged 06 idles at -18 lb/ft I dont think thats a problem, but as soon as I get moving I see it going into positive numbers.
Your MAF charge seems low, I get around 42 lbs.
Has the throttle body model been retuned? I dont think it matters that its upside down.
Have you checked for vacuum leaks?

[Thatwhite5.0]

I'll post that up soon. The guy had to drive 2 hours to get here. I had to drive 2 hours to his city for a different reason but met up with him to check the maf. I'll post a log and pics. Like I said, its something with the calculation of airflow.

It datalogs 20# max at wot.
It only calculates 130ft lbs max at wot.
It only see .5 load max at wot.

He dynod 370whp. The throttle body is stock, just upside down. Those logs are coming with on 15 minutes

[Thatwhite5.0]

Here is a log and tune. This is the tune pulled from the vehicle. I highly highly advise no one use any of the tune file as an example.

pids-reading-weak.hpl
STOCK-file.hpt

[decipha]

if the iat was in the intake after the blower it was measuring actual intake air temps.

if im understanding correctly you moved it to the maf before the blower now? if so thats not safe since you wont be able to have any act retard and have no way of knowing what your actual air charge temps are

On fords the load number is up to the tuner to put where ever they want. Check out the spark table axis scaling to see if thats how they had it setup. The load with failed maf table will let you know as well if the tuner dialed it in properly.

if all checks out and you want a higher load number just scale sarchg spark and fuel scaling to what ever new load value you desire.

[CCS86]

On fords the load number is up to the tuner to put where ever they want.

Can you qualify this statement?

Where in the tune can you directly control the calculated load / air load, on a Copperhead PCM?

[veeefour]

On fords the load number is up to the tuner to put where ever they want.

Same as torque.

[CCS86]

Same as torque.

No, not really.

You can define the load:TQ:rpm relationship however you want, but you can't change the PCM's indicated TQ. So if you change TQ tables in a way that doesn't match the PCM's calculation of indicated TQ, it causes driveability issues.

[SultanHassanMasTuning]

the tune was not oddly scaled?

[veeefour]

No, not really.

You can define the load:TQ:rpm relationship however you want, but you can't change the PCM's indicated TQ. So if you change TQ tables in a way that doesn't match the PCM's calculation of indicated TQ, it causes driveability issues.

Yes, really like 1000%.

LOAD is free to control with SD model, TORQUE is free to control with Torque Model - everything is scaled through ETC and Driver Demand. Period.

[CCS86]

Yes, really like 1000%.

LOAD is free to control with SD model, TORQUE is free to control with Torque Model - everything is scaled through ETC and Driver Demand. Period.

Okay, if you feel like you have a mastery of this system, see if you can connect these dots for me:

WOT, 5000 rpm, 100% weighting of OP, air load 1.576:

Inverse table: 682
TQ Table: 580
ETC TQ: 588
Scheduled TQ: 641
Engine Brake TQ: 504

[murfie]

Can you qualify this statement?

Where in the tune can you directly control the calculated load / air load, on a Copperhead PCM?

I'm just going to attached a pic of a spreadsheet with the general idea of scaling your load. Generally you tell the PCM the MAF transfer is half of its real values and the injectors are half of their real values, or any other scalar, and that is what the load value will do. It's a technique not needed in later fords as you can manipulate the axis's of tables to scale them instead, and can keep the load near its true value. Many other stock ECU's you are stuck with the axis values given to you by HPT and the OEM.

load scaling.PNG

MAF transfer and injector data are critical in this. MAF tube, Fuel system installation need to be properly reflected into the calibration or you will go down a rabbit hole you don't want to go down, of getting axis scaling and load scaling to match up happily. Because you have control over both is what makes Fords "hard to tune" for most people. They will use axis scaling in some parts and load scaling in others, or they will just mistakenly get the scaling/ interpolation math wrong.

Simply put:
Pedal(APP)& Desired torque value can give you a MAF value.
You MAF sensor value can give you a engine Torque value.
Idle airflow(MAF)& target RPM can give you a torque value that the base torque starts from and returns too.
0-100% torque demand for pedal.
idle MAF to Peak WOT MAF from MAF sensor.

[CCS86]

Sure you can lie about both air a fuel delivery, proportionally, to maintain accurate PW with skewed values for load/TQ... but why?

If we can rescale axis values on the Copperhead, why would you ever want to do this? I can't see any benefit.

[B E N]

This isn't a copperhead.

OP can you pull your injector part numbers and post them please.

[Thatwhite5.0]

This isnt my tune or my install.
The owner said the shop installed 47lb injectors. The injectors have Siemens deka labeled on them but the injector calibration was stock except 3 parameters.

They did cut two wires from the MAF for IAT. They wired in their own IAT sensor in the back if the manifold on the passenger side.

Load, torque, maf #s is up to the tuner. Changing all parameters in this file did nothing. The datalogs are less than half of what they should be and I couldn't get a change in that. Not even wiring the iat back to stock location. I told the owner to buy new injectors. This is one of the unknowns about the install.

[veeefour]

This isnt my tune or my install.
The owner said the shop installed 47lb injectors. The injectors have Siemens deka labeled on them but the injector calibration was stock except 3 parameters.

They did cut two wires from the MAF for IAT. They wired in their own IAT sensor in the back if the manifold on the passenger side.

Load, torque, maf #s is up to the tuner. Changing all parameters in this file did nothing. The datalogs are less than half of what they should be and I couldn't get a change in that. Not even wiring the iat back to stock location. I told the owner to buy new injectors. This is one of the unknowns about the install.

Have you tried LU47 data?

[CCS86]

The IAT wiring sounds like "normal" practice for people running a supercharger with a strategy that doesn't support the MCT switch.

You just send the IAT2 (manifold) sensor data to the MAF harness, so that IAT1 reads manifold charge temp. That's not going to cause any scaling issues.

[CCS86]

This isnt my tune or my install.
The owner said the shop installed 47lb injectors. The injectors have Siemens deka labeled on them but the injector calibration was stock except 3 parameters.

Which 3 parameters?

If someone installed bigger injectors without changing the injector data, then "fixed" fueling with the MAF transfer function, that would cause scaling issues.