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Discussion Starter · #1 · (Edited)
Hello,

I'm helping my friend with his MSpnp2 installation. He has a 1991 5.0 AOD and is upgrading to a 351W engine. Combo is as follows:

  • 351W roller block
  • AFR 185 heads
  • Not sure on compression, but built for naturally aspirated
  • 1.6 roller rockers
  • Stock Ford ignition and TFI mounted on a Ford distributor
  • TFS intake manifold
  • 42 Lb/hr green top injectors (eBay, so we'll see how these work out)
  • BBK in fender CAI
  • 1994 Cougar 3.8L MAF
  • 70mm BBK TB
  • Custom cam, high 220's duration at 0.050" and mid .550" lift both intake and exhaust, low 110's LSA
  • Single electric fan
  • 1 5/8" long tubes with O/R X-pipe into Spintech mufflers
  • Beefed up AOD, 2600ish stall
  • 4.10 gears
This is my first experience with Megasquirt and TunerStudio. I have several years with GM LSx based computers and I have some experience with the Quarterhouse and TunerPro on my own car. I read as much as I could on the MS platform and what needed to be done to get the car to run with it. He wants to keep the MAF and have the MS control the electric fan. The MS he bought is from DIYAutotune and the model number is MCPNP2-EEC4A8, fw rev .3.3.1, inside the base board is version 1.2 and the green board is version 1.3b.

We will be using some of the wires coming from the options plug:

  • Wire 05 - Chassis ground. Should this wire be grounded to where the factory A9P was grounded?
  • Wire 13 - Launch control input. I'm using this for my A/C idle up input. I moved jumper J3 in the MS and it will be tied into pin 10 of the EEC harness.
  • Wire 19 - MAF sensor signal. I installed a jumper inside the MS from the external MAP pin to the ADC1 pin. Option wire 19 will be connected to pin 50 of the EEC harness.
  • Wire 21 - Oxygen sensor input. My friend had an Autometer WBO2, so the blue + analog output wire from the WB will go here. I did change jumper J6 in the MS to reflect this.
  • Wire 22 - Signal Ground. Here I'll connect the - black analog output wire from the WB and the MAF pin 9 wire from the EEC connector.
  • Wire 24 - Output 1 relay control. This wire I'm going to connect to the fan relay 85 terminal, the one that would be on the other side of the relay coil 86 that is getting a 12V switched +. We are also going to use a second relay to turn on the fan with a signal from the A/C clutch from pin 10 of the EEC connector.
  • Wire 25 - Output 2 relay control. We are going to use this one for the A/C WOT cutoff relay and connect it to pin 54 of the EEC connector.
Does the above wiring seem correct, or are these some changes you would recommend?

I'm also attaching a base tune file that I put together to reflect all the information above. Could someone please take a look at it and comment on any changes that I need to make?

* I had to change the file extension in order to attach it. If you just delete the .pdf you should be able to open it. *
 

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It is kind of uncommon to keep the maf. Honestly I highly doubt you’d even notice a difference in drivability between maf or no maf. His choice though.

I’ll check out the tune tonight when I get home. I have a pimp non sequential tune file if you want a copy of it too, I’m sure they’re similar.

Far as grounds go, I just grounded the controller to a clean spot on the engine secluded from other wiring.
 

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Discussion Starter · #3 ·
It is kind of uncommon to keep the maf. Honestly I highly doubt you’d even notice a difference in drivability between maf or no maf. His choice though.

I’ll check out the tune tonight when I get home. I have a pimp non sequential tune file if you want a copy of it too, I’m sure they’re similar.

Far as grounds go, I just grounded the controller to a clean spot on the engine secluded from other wiring.
Thank you, I would love to take a look at your file. He wants to keep the MAF as he wants the ECM to know the ctual amount of air entering the engine, not have the computer "guess" based on a table. I will be helping him tune the VE table as well and probably run a blend of the two, use MAF for fuel and VE (load) for spark calculations.
 

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Thank you, I would love to take a look at your file. He wants to keep the MAF as he wants the ECM to know the ctual amount of air entering the engine, not have the computer "guess" based on a table. I will be helping him tune the VE table as well and probably run a blend of the two, use MAF for fuel and VE (load) for spark calculations.
Here's what is included for a stock ish build. Shoot, nevermind it won't attach. Let me see why not.

Sounds like what pro-m says to sell their MAF based efi lol. Total waste of time for 99% of people to set up a maf curve. The VE table in MS will handle fueling far better than a "guess"
 

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Looking at the tune you have, the IAC open/close appears to be set to inverted. I've never seen it that way on 5.0 fords. I also like to use injector squirts per cycle to 2 on batch fire stuff.
 

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Discussion Starter · #6 ·
Looking at the tune you have, the IAC open/close appears to be set to inverted. I've never seen it that way on 5.0 fords. I also like to use injector squirts per cycle to 2 on batch fire stuff.
Thank you for taking a look at my file. I have not touched the IAC settings, that's how they were from the base file, so I figured that they were correct to get the car running. I'll do some searching on the topic. I'll go ahead and change the injector squirts from 4 to 2.

I found the MAF curve on efidynotuning.com, so hopefully that is solid information to get the tuning process started.
 

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It is kind of uncommon to keep the maf. Honestly I highly doubt you’d even notice a difference in drivability between maf or no maf. His choice though.

I’ll check out the tune tonight when I get home. I have a pimp non sequential tune file if you want a copy of it too, I’m sure they’re similar.

Far as grounds go, I just grounded the controller to a clean spot on the engine secluded from other wiring.
It's uncommon, but not unknown to those with forced induction. I've been using both for a long time & did notice an immediate difference in drivabilty.
Basically, you use maf for fuel & map for spark.
 

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Thank you, I would love to take a look at your file. He wants to keep the MAF as he wants the ECM to know the ctual amount of air entering the engine, not have the computer "guess" based on a table. I will be helping him tune the VE table as well and probably run a blend of the two, use MAF for fuel and VE (load) for spark calculations.
That's the way to do it.
If you want to use MAF, set VE table to 100 for all cells.
Remember to input the curve for you MAF.
 
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