TDStuart Tuning Adventure

[GregO]

So am learning that if I want to start tuning my car myself using pcmtec (or hpt or anything really), that I’m best off doing one change at a time and getting that to work and move on to the next instead of like 9 things at once.

Performance tuning 101.

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[tdstuart]

I use duct tape and tape the gauge to the windshield and do a 3rd gear pull.

The problem is I need to ford quick connect fitting for the fuel system so I can tap into it. I don’t see those with the autozone kit

 

[markmurfie]

With the DW400 we have no idea what FP you are actually running. I emailed you a 2009 GT500 cal. It is scaled for 39 base FP but ranges from 20psi to 70psi. Try those.

If no improvement go back to Roush and tune the MAF. If you get stumbles or surging you know you will have to tune the injectors.

I think Autozone rents (for free) fuel pressure gauges.

How are you guys doing the MAF 2 LOAD calculations? I'm not getting it to work.

The fuel pressure will be near 58psi as that's what the pressure release in the fuel tank is. Now the pump could be over running that, but it isn't going to be by much because the pump is either low or high depending on fuel demands to not heat up the fuel.

I think the PMAS MAF and either the Ford racing data or Roush tune data provided good enough results to work from. Multiplying the first racing data made it go 2-10% lean.
I'm not sure needing to know the FP is needed.

Mike mentioned SD, I wouldn't think that would limit an NA application. There could be IPC limits to torque values a stock NA application could reach.

The MAF to Load calculation is simple I derived it my self and then I found it in a Ford patent years ago confirming that's what they use. They have a much more complicated way of doing for Cylair anticipation, but that's not of concern.

Take the engines air flow rate in pounds per Minute and divide the rotation rate in RPM. The minute units cancel and you get pounds per revolution. Knowing half the cylinders will perform a intake event per revolution you can divide pounds per revolution by intaking cylinders per revolution. The revolution units cancel and you are left with airmass pounds per cylinder. This airmass can be used in the SD to get inferred MAP.
To get air load you just divide that by the "engine cylinder displacement" .00167 in 15-17 and .00170 in Gen 3.

 

[tdstuart]

The fuel pressure will be near 58psi as that's what the pressure release in the fuel tank is. Now the pump could be over running that, but it isn't going to be by much because the pump is either low or high depending on fuel demands to not heat up the fuel.

I think the PMAS MAF and either the Ford racing data or Roush tune data provided good enough results to work from. Multiplying the first racing data made it go 2-10% lean.
I'm not sure needing to know the FP is needed.

Mike mentioned SD, I wouldn't think that would limit an NA application. There could be IPC limits to torque values a stock NA application could reach.

The MAF to Load calculation is simple I derived it my self and then I found it in a Ford patent years ago confirming that's what they use. They have a much more complicated way of doing for Cylair anticipation, but that's not of concern.

Take the engines air flow rate in pounds per Minute and divide the rotation rate in RPM. The minute units cancel and you get pounds per revolution. Knowing half the cylinders will perform a intake event per revolution you can divide pounds per revolution by intaking cylinders per revolution. The revolution units cancel and you are left with airmass pounds per cylinder. This airmass can be used in the SD to get inferred MAP.
To get air load you just divide that by the "engine cylinder displacement" .00167 in 15-17 and .00170 in Gen 3.

What is SD?

Coyote cookbook should be here Monday and hopefully I learn more of these terms

 

[markmurfie]

What is SD?

Coyote cookbook should be here Monday and hopefully I learn more of these terms

Speed density.

It's the calculation of airflow based on manifold pressure and temperature. Some cars will not have a MAF sensor, but a manifold pressure sensor. When your car has a MAF, it uses it to calculate the manifold pressure from it.

 

[tdstuart]

Speed density.

It's the calculation of airflow based on manifold pressure and temperature. Some cars will not have a MAF sensor, but a manifold pressure sensor. When your car has a MAF, it uses it to calculate the manifold pressure from it.

Makes sense thank you. When you are doing the calculations in vcm scanner is there a way to pull up the sd info like you mentioned for the calculations?

I was using a simplified on engineer Mike posted on the hptuners forums

 

[K4fxd]

SD is speed density.

 

[GregO]

I’ve had some weird iat readings with the fenderwell kit. I have a video of the iats randomly dropping like 20* while driving on the free way and jumping back up and down wildly.

Did I miss the solution to the 20° temp swing ?
What was the actual max IAT recorded before the Temperature drop ?

 

[K4fxd]

Did I miss the solution to the 20° temp swing ?

No, he still has a suspect MAF sensor.

 

[markmurfie]

Makes sense thank you. When you are doing the calculations in vcm scanner is there a way to pull up the sd info like you mentioned for the calculations?

I was using a simplified on engineer Mike posted on the hptuners forums

If I recall correctly the cook book briefly mentions Speed density and says something like "most times just zero this out"... Then leaves it at that's.

The guy who wrote the cook book posted more about the calculation on HPT, but it wasn't very helpful in understanding it.

The stickied post on the Ecoboost section is the most helpful thing you can read. They need to understand it as they have MAP sensors not MAF sensors.

 

[tdstuart]

Did I miss the solution to the 20° temp swing ?
What was the actual max IAT recorded before the Temperature drop ?

It was jumping up and down a bit. Saw it get like 15-20* under ambient then after a while it went back to normal and the next drive it seemed normal. I tried uploading a video of it

 

[GregO]

No, he still has a suspect MAF sensor.

Or possibly my hypothetical. His current sensor worked fine for the JLT.

 

[K4fxd]

@tdstuart

Gregg might have something. Try the JLT intake and see if your MAF 2 load fixes.

 

[tdstuart]

@tdstuart

Gregg might have something. Try the JLT intake and see if your MAF 2 load fixes.

I really don’t want to take that intake off again

I’m gonna pickup a new maf sensor

I think either I or my friend has my stock injectors. I would rather change the injectors to test stuff than the intake

 

[K4fxd]

I think either I or my friend has my stock injectors. I would rather change the injectors to test stuff than the intake

Changing intakes is cheaper than buying a quality MAF sensor.

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