2007 GT500 MAF tuning, Roots Blown & Turbo

[5.0Thunder]

EDIT: MS2 V3.57 with 3.4.2 firmware for reference

Entertaining the idea of welding a MAF sensor mounting pad to my 3.5" intake tube (draw through) and seeing if it helps me tune my roots supercharged car quicker. I've located a 2007 GT500 Slot MAF sensor which, from what I read, works really well in draw through and blow through applications (below 600hp especially) so the plan is to weld the mounting pad on a straight section of the tube, use either the OEM transfer function or get a revised transfer function for 3.5" tube diameter (the stock tube may be 3.5" so I'll see what I need to do here), wire it to the ECU, then see what she does. If all goes well with that, I'll weld another pad on my turbo car and try it there too. I like the idea of using a MAF for cruising and simplistic tuning. Both cars use the internal MAP sensor and the turbo car has been great but my time has become limited lately so I'd like to see if this helps get quicker tune on the supercharged car.

I know Blown88GT uses and enjoys his MAF setup so I'd like to give it a go.

Any big concerns or reasons to turn away from this idea?

[fntwisted1]

you should have no trouble with this plan. just do the transfer like normal for the maf. keep us posted

[5.0Thunder]

These sensors appear to have intake temperature sensors as well so I could use the MAF IAT for all conditions below boost and use the manifold sensor while in boost (with high air flow) so maybe I can get some accurate temp readings for proper fueling.

[Blown88GT]

This looks like the sensor. SCT would have the transfer function (calibration curve).
https://www.americanmuscle.com/sct-ba-5000-maf.html
Look at the customer pics.
You should be able to find an 05-10 GT factory MAF/housing in a salvage yard.

BTW, I recently gave Auto Tune (VEAL) another go.
Many low load cells are well above 100. VE is greater than 100 because BOV not large enough to vent 100%.
Could be why your turbo has been easier to tune than the supercharger.

[5.0Thunder]

This looks like the sensor. SCT would have the transfer function (calibration curve).
https://www.americanmuscle.com/sct-ba-5000-maf.html
Look at the customer pics.
You should be able to find an 05-10 GT factory MAF/housing in a salvage yard.

BTW, I recently gave Auto Tune (VEAL) another go.
Many low load cells are well above 100. VE is greater than 100 because BOV not large enough to vent 100%.
Could be why your turbo has been easier to tune than the supercharger.

The Sensor for the GT500 is Ford # 4G7Z-12B579-AB, like shown in this link..

https://www.lethalperformance.com/letha ... e-maf.html

Should be plenty good for my draw through roots blower application.

Good point about the VEAL showing high VE values at light load. My roots system obviously has no BOV so maybe it's a similar case for me.

[5.0Thunder]

So from EECTuning (Decipha?), I was able to get data on the 07GT500 maf sensor from PMAS, which I assume to be in a stock housing/intake.

Stock '07 GT500 - PMAS

Voltage Flow (kg/hr)
16.00 1890
5.000 1890
4.759 1611.72
4.513 1375.40
4.263 1175.78
4.022 1005.81
3.818 860.24
3.602 735.69
3.402 632.16
3.214 541.45
3.030 463.80
2.856 397.54
2.686 340.14
2.362 250.01
2.072 185.16
1.802 135.05
1.683 117.04
1.444 85.20
1.329 72.71
1.227 62.35
1.149 54.85
1.009 43.01
0.935 37.74
0.859 32.90
0.762 27.45
0.671 22.98
0.521 17.34
0.345 12.11
0.254 10.11
0.000 0

I can convert the units to get grams/second for tunerstudio, then scale these values by the %difference between OEM intake diameter and my 3.5" tube (may end up being same). I'll then take my VE table and make every cell 100, and start the tuning process. I think it's also a good idea to utilize this MAF IAT sensor so I can use a SPARE input at the connector and use MAF IAT data for cruise and Manifold IAT data for anything above 100KPA.. Does this sound reasonable?

[Blown88GT]

Your numbers are from the forum, not the calculator.
https://eectuning.org/forums/viewtopic. ... es#p117729
Doesn't agree with any of these.
http://www.efidynotuning.com/maf.htm
I think you want this one: OEM Slot 3 - 1/2" - 90mm

I have doubts about his calculator if they don't match anything on his forum.
Use a known housing with published flow data or you will never have a valid baseline.
Having only the sensor does you little good. Making your own housing will only work if you have a flow bench to calibrate it.

[ashford]

a common slot sensor in a 4" tube is almost spot on with the lightnening curve which comes with every ms3 release as an msq.part

[5.0Thunder]

Your numbers are from the forum, not the calculator.
https://eectuning.org/forums/viewtopic. ... es#p117729
Doesn't agree with any of these.
http://www.efidynotuning.com/maf.htm
I think you want this one: OEM Slot 3 - 1/2" - 90mm

I have doubts about his calculator if they don't match anything on his forum.
Use a known housing with published flow data or you will never have a valid baseline.
Having only the sensor does you little good. Making your own housing will only work if you have a flow bench to calibrate it.

Interesting, I didn't see the forum posts but they are indeed different. Since PMAS posted in the forum, I think that'd be most accurate. I went ahead and emailed a few maf suppliers that have experience with these sensors to see what they could provide. It sounds like they've tested these sensors in a variety of tube diameters so there should be some reliable data out there. The 3-1/2" data looks different than all the other stuff too.

a common slot sensor in a 4" tube is almost spot on with the lightnening curve which comes with every ms3 release as an msq.part

At this point I feel like it'd be best to get data from somebody who has tested them. One concern is the lack of resolution in their table. They'll have somewhere around 30 data points where the TS table has 64. I haven't figured out how to take the 30 points and expand them in to 64 yet but I'm thinking it may not be necessary. I can make all the extra cells 0 or max I think.

[Blown88GT]

a common slot sensor in a 4" tube is almost spot on with the lightnening curve which comes with every ms3 release as an msq.part

His signature says MS2 for both vehicles.

...One concern is the lack of resolution in their table. They'll have somewhere around 30 data points where the TS table has 64. I haven't figured out how to take the 30 points and expand them in to 64 yet but I'm thinking it may not be necessary. I can make all the extra cells 0 or max I think.

My transfer function only had 25 data points. TS for MS2 had 50, now has 64. I used Excel to interpolate data points in between the 25. TS fills in the remaining upper values all the same. TS now has an interpolate key, so Excel not needed. You still might like Excel to convert to g/sec.

Some here, said to tune the curve, but I believe it's better to tune the VE & leave the base curve alone.
Here's a screen shot what mine looks like, table shows the upper end.
Notice that the curve is exponential. Yours will have different values but it will still be exponential.
If you look carefully, there's a slight rise around 3.2V. Don't know why that is, but it's minor.

It's critical that whatever transfer function you use has the same sensor & same housing that you intend to use.

[5.0Thunder]

a common slot sensor in a 4" tube is almost spot on with the lightnening curve which comes with every ms3 release as an msq.part

His signature says MS2 for both vehicles.

...One concern is the lack of resolution in their table. They'll have somewhere around 30 data points where the TS table has 64. I haven't figured out how to take the 30 points and expand them in to 64 yet but I'm thinking it may not be necessary. I can make all the extra cells 0 or max I think.

My transfer function only had 25 data points. TS for MS2 had 50, now has 64. I used Excel to interpolate data points in between the 25. TS fills in the remaining upper values all the same. TS now has an interpolate key, so Excel not needed. You still might like Excel to convert to g/sec.

Some here, said to tune the curve, but I believe it's better to tune the VE & leave the base curve alone.
Here's a screen shot what mine looks like, table shows the upper end.
Notice that the curve is exponential. Yours will have different values but it will still be exponential.
If you look carefully, there's a slight rise around 3.2V. Don't know why that is, but it's minor.

It's critical that whatever transfer function you use has the same sensor & same housing that you intend to use.

I'm currently liking the idea of getting an accurate curve and trimming the VE table. The GT500 data from the calculator page appears to match the forum data, just using different voltage data points. I'm not sure how his calculator came up with this but it seems that both are the same when graphed side by side and finding a few matching points to check against. I'm still waiting on some replies from PMAS, PRO-M, and SCT but my parts should arrive early next week so maybe I can have it going by the following weekend.

Any idea on what the Sensor Range should be in the MAF Settings dialog? The maf only goes to 525 g/s at 5v so I chose 650g/s from the drop down. There's a 2600g/s option and I've never heard of a 3600hp maf sensor lol

[Blown88GT]

...
1. I'm currently liking the idea of getting an accurate curve and trimming the VE table.
2. Any idea on what the Sensor Range should be in the MAF Settings dialog?
3. The maf only goes to 525 g/s at 5v so I chose 650g/s from the drop down. There's a 2600g/s option and I've never heard of a 3600hp maf sensor.

1. The VE Table is more intuitive, since all cells start at 100. Effectively, it displays volumetric efficiency percentage.

2. Always read the entire "tool tip".
MAF Sensor Range
Sets the range to match your MAF sensor. Set this before loading a MAF calibration curve. On gasoline, 650g/s ~800hp; 1300g/s ~1600hp; 1950g/s ~2400hp and 2600g/s ~3200hp. Use the lowest range suitable for better low-end precision.

3. 525 g/s @ 5.0V is much better than the OEM Ford 55mm sensor, which is about half that.
It was designed over 30 years ago. The newer slot sensors are far superior. If I were racing, I would get a new MAF/sensor. I'm not concerned since I will never operate in that region. I have several spare OEM Ford 55mm sensors & housings from salvage yard. You can't find these any more.

BTW, have you actually wired your MS2 for a MAF? If you configure a MAF gauge on TS dashboard, you'll know for sure if it's reading it.

[ashford]

a common slot sensor in a 4" tube is almost spot on with the lightnening curve which comes with every ms3 release as an msq.part

His signature says MS2 for both vehicles.

...One concern is the lack of resolution in their table. They'll have somewhere around 30 data points where the TS table has 64. I haven't figured out how to take the 30 points and expand them in to 64 yet but I'm thinking it may not be necessary. I can make all the extra cells 0 or max I think.

i caught on that it is an ms2 just pointing out that ms3 firmware ships with a lightening curve that can be transfered over and that a slot in a 4" od pipe is nearly identical. also the lightening maf is relatively cheap and still available from the original manufacturer.

http://www.rockauto.com/en/catalog/ford ... ensor,5128

the hitachi unit MAF0046 is the manufacturer for ford, the part just has the ford part number ground off

[Blown88GT]

...i caught on that it is an ms2 just pointing out that ms3 firmware ships with a lightening curve that can be transfered over and that a slot in a 4" od pipe is nearly identical. also the lightening maf is relatively cheap and still available from the original manufacturer.

http://www.rockauto.com/en/catalog/ford ... ensor,5128

the hitachi unit MAF0046 is the manufacturer for ford, the part just has the ford part number ground off

Hitachi did the original ones for Ford.
Understand what you're pointing out, now. You also had me confused with "lightening maf", as in the F150 Lightning.
The housing & sensor for $82? It doesn't appear to be a slot-type sensor. Looks just like the old 55 or 65mm housing/sensor.
Slot sensors are on the axis of the diameter.
Unfortunately, when it comes to flow data, "nearly identical" is not good enough. I have flow data from housings that are identical, except for the screen & flow data is different.
Is the housing the same size as the original Ford 55mm? It has a flange, which myself & OP cannot fit. Looks like plastic, not aluminum.
How do you get the curve out of MS3? I see no selection for a Lightning curve.
I have an MS3 project for My Car.

[ashford]

...i caught on that it is an ms2 just pointing out that ms3 firmware ships with a lightening curve that can be transfered over and that a slot in a 4" od pipe is nearly identical. also the lightening maf is relatively cheap and still available from the original manufacturer.

http://www.rockauto.com/en/catalog/ford ... ensor,5128

the hitachi unit MAF0046 is the manufacturer for ford, the part just has the ford part number ground off

Hitachi did the original ones for Ford.
Understand what you're pointing out, now. You also had me confused with "lightening maf", as in the F150 Lightning.
The housing & sensor for $82? It doesn't appear to be a slot-type sensor. Looks just like the old 55 or 65mm housing/sensor.
Slot sensors are on the axis of the diameter.
Unfortunately, when it comes to flow data, "nearly identical" is not good enough. I have flow data from housings that are identical, except for the screen & flow data is different.
Is the housing the same size as the original Ford 55mm? It has a flange, which myself & OP cannot fit. Looks like plastic, not aluminum.
How do you get the curve out of MS3? I see no selection for a Lightning curve.
I have an MS3 project for My Car.

the housing is huge around 90mm id. i think this is the flange for it https://www.spectreperformance.com/sear ... ?prod=8146
i don't know it this would work well in blow through or not.
the curve for this sensor is so close i used it initially for a slot in a 4' tube and my trim table from autotune was was within 15% . if he is using a 3.5 tube it will need to be scaled down.

the flow data is in the ms3 firmware download look in tune files folder and there will be an msq.part you can open and it populates an open ms3 tune in tuner studios.

[5.0Thunder]

All good info. Like I said, I'm hoping the suppliers have accurate data for my sensor in a 3.5" tube so I don't have to make adjustments or scale 4" data. If I have to scale it, not an issue, so long as the 4" test data is still accurate. Then I can trim the VE table as mentioned above.

In the interest of "budget" building, I want to point out that I found a Genuine OEM GT500 take-off MAF from an 09 GT500 for $30 shipped (only factory and dealership miles on it). I've seen similar sensors sell for anywhere from $60-$100 used and roughly $150 new. The connector for this 6 pin MAF was $15 and the flange is a simple weld-on flange for $20, similar to what Ashford mentioned. I should be all in at around $65 plus any circuit I have to build within the ECU to accept the MAF input (couple of dollars I suspect). Cheaper and hopefully better than the Lightning MAF/Housings that I was seeing for sale. In the factory housing, this sensor is capable of more horsepower than my car should produce but still have plenty of low-flow resolution, so I think this is a great option for me. As far as I know, this is a great price for the advantages of the setup.

[Blown88GT]

Cool. It's very close to my 76mm C&L & green calibration tube with Ford 55mm sensor.
I'm blow-thru now which is why a 42lb cal tube with 30lb injectors.
No new circuits required for the ECU, since already 5V.
4 or 6 pin connector has the same 4 to the MAF.
MAF Signal to ECU Analog 1 or 2
MAF Signal Return to ECU Signal Ground
MAF 12V Power to ECU 12V
MAF 12V Ground to ECU 12V Ground

[5.0Thunder]

Cool. It's very close to my 76mm C&L & green calibration tube with Ford 55mm sensor.
I'm blow-thru now which is why a 42lb cal tube with 30lb injectors.
No new circuits required for the ECU, since already 5V.
4 or 6 pin connector has the same 4 to the MAF.
MAF Signal to ECU Analog 1 or 2
MAF Signal Return to ECU Signal Ground
MAF 12V Power to ECU 12V
MAF 12V Ground to ECU 12V Ground

Thanks for the pin breakdown. It'll also have two for IAT so I'm thinking about wiring those up as well. I'd like to see if there's a way to use the MAF IAT during idle and cruise then switch to Manifold IAT under higher flow scenarios. It'd require the new IAT input to be added and some sort of switching program to be added.

[Blown88GT]

Thanks for the pin breakdown. It'll also have two for IAT so I'm thinking about wiring those up as well. I'd like to see if there's a way to use the MAF IAT during idle and cruise then switch to Manifold IAT under higher flow scenarios. It'd require the new IAT input to be added and some sort of switching program to be added.

I have 2 sensors, the OEM one in the manifold & one between the MAF & the Throttle Body, which is the one I'm using. I would just use the MAF IAT, you don't need the other one. I have a lot of piping between the I/C outlet & the TB. The MAF is in a long straight section inside the fender behind the passenger side headlamp, below where the battery is located on mine (same as the 4 cyl). IAT is where the piping enters the engine compartment. I extended the factory harness, so can revert, if needed.

[5.0Thunder]

Thanks for the pin breakdown. It'll also have two for IAT so I'm thinking about wiring those up as well. I'd like to see if there's a way to use the MAF IAT during idle and cruise then switch to Manifold IAT under higher flow scenarios. It'd require the new IAT input to be added and some sort of switching program to be added.

I have 2 sensors, the OEM one in the manifold & one between the MAF & the Throttle Body, which is the one I'm using. I would just use the MAF IAT, you don't need the other one. I have a lot of piping between the I/C outlet & the TB. The MAF is in a long straight section inside the fender behind the passenger side headlamp, below where the battery is located on mine (same as the 4 cyl). IAT is where the piping enters the engine compartment. I extended the factory harness, so can revert, if needed.

Good idea extending the harness. This roots blown car has a custom harness that I put together when installing the ECU/blower/etc. and I may be able to use the existing IAT wires if the sensor is within close proximity. If not, I can extend them. Worst case, I run new wires, not a big issue regardless.

First hiccup: Pigtail connector that I bought is backwards.. The "Keyed" slot on the connector is on the wrong side so my maf won't plug in. Everything else appears to be identical and most other connctors I see appear to have the slot in the right location sooooo I'm probably going to source a different one (ron francis maybe). I wish I had a scrap yard nearby that I could snip one out of.