Stock vs Tuned vs JLT vs PMAS - The Real Dyno Test!

[4V Mayhem]

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[RomanB]

Cannot use the same tune on the JLT as the PMAS. If the PMAS is the no tune version, you have to use stock airbox maf transfer, which is different from the JLT transfer... if the PMAS is the tune version... you STILL have to use a different MAF transfer on the PMAS than the JLT. Test invalid.

Everything within the tune is the same besides the MAF transfer rate. So yes it is the same tune. MAF transfer rates won't affect how much power will be made, all it does is make sure the air being metered is accurate, not how much is flowing. Timing tables, fuel, cam timing will all be the same, on the same car.... it is as valid as a test can get.

 

[Terminator2]

Cannot use the same tune on the JLT as the PMAS. If the PMAS is the no tune version, you have to use stock airbox maf transfer, which is different from the JLT transfer... if the PMAS is the tune version... you STILL have to use a different MAF transfer on the PMAS than the JLT. Test invalid.

If all other tune aspects other than MAF vs period are the same this is perfectly valid test.

 

[markmurfie]

Everything within the tune is the same besides the MAF transfer rate. So yes it is the same tune. MAF transfer rates won't affect how much power will be made, all it does is make sure the air being metered is accurate, not how much is flowing. Timing tables, fuel, cam timing will all be the same, on the same car.... it is as valid as a test can get.

You're joking right? The various tables work off of torque and load. It gets the calculated load from the MAF transfer values. The MAF value is filtered with a compare to the speed density calculations which can help a bit because those will be the same. The point is a different MAF transfer will tell the ECU to use different loads at different amounts of air flows hence the cam positions, spark, and the rest will be different. Not much different from an tuned intake, but different. The miss understanding of this is probably what leads people to thinking the stock air box is as good as a larger less restrictive one as all they think they need to change is the MAF transfer.

 

[Terminator2]

You're joking right? The various tables work off of torque and load. It gets the calculated load from the MAF transfer values. The MAF value is filtered with a compare to the speed density calculations which can help a bit because those will be the same. The point is a different MAF transfer will tell the ECU to use different loads at different amounts of air flows hence the cam positions, spark, and the rest will be different. Not much different from an tuned intake, but different. The miss understanding of this is probably what leads people to thinking the stock air box is as good as a larger less restrictive one as all they think they need to change is the MAF transfer.

If both transfer values are accurate this is all moot. None of the calculated values or tables used by the ecm at wide open throttle will change.

 

[markmurfie]

I guess I just don't think correcting the maf from the lambda sensor yeilds accurate flow values. Close sure. Not accurate enough to compare the difference between two intakes. You need a mad calibrated on a flow bench for that. Pmas has done this.

 

[RomanB]

I guess I just don't think correcting the maf from the lambda sensor yeilds accurate flow values. Close sure. Not accurate enough to compare the difference between two intakes. You need a mad calibrated on a flow bench for that. Pmas has done this.

Thank god they are using a dyno and not just comparing MAF lb/min flow values

 

[Taneras]

Thank god they are using a dyno and not just comparing MAF lb/min flow values

From our perspective they might as well be rolling chicken bones. It's almost been a week and nada...

 

[Bluemustang]

What does the MAF lb/min show? Is this an inferred value based on some other measurement?

 

[RomanB]

What does the MAF lb/min show? Is this an inferred value based on some other measurement?

http://www.mustang6g.com/forums/showthread.php?t=65494&highlight=Maf+flow

 

[markmurfie]

What does the MAF lb/min show? Is this an inferred value based on some other measurement?

The Maf sensor works by heating up a wire to a certain temperature. As air passes over that wire the voltage/ frequency varies to maintain that temperature. In the case of the newer digital MAF sensors its not voltage varying it frequency. The inverse of this frequency gives you what is know as the period(yes this is a length of time). In the ECU this period is assigned a flow rate. When you change the size of the tube the MAF sensor is in the associated flow values change for any given period. The new air flow values are determined by applying the error of the Air fuel ratio the lambda sensor is seeing. This method is okay to get things working. As you can see, you are correcting air flow rate by measuring oxygen content after it has gone through the engine and fuel is used to burn it and you only know the amount of fuel you used. That is not very accurate as combustion with each engine cycle varies due to inconsistent burns. Ford used a flow bench to scale their MAF values and still compared it to a speed density calculation just to be that much more accurate.

 

[DarkestHour]

Mark, all that needs to happen is for Beefcake to share the logs on datazap or something and then we can all see if the cam positions, timing, and other variable are different between the runs. That will set your mind at ease.

 

[mustang_guy]

Mark, all that needs to happen is for Beefcake to share the logs on datazap or something and then we can all see if the cam positions, timing, and other variable are different between the runs. That will set your mind at ease.

His mind seems to be at ease. Looks like hes correcting what looks to be misinformation

 

[markmurfie]

Mark, all that needs to happen is for Beefcake to share the logs on datazap or something and then we can all see if the cam positions, timing, and other variable are different between the runs. That will set your mind at ease.

We will not see logs from these. I wouldn't want to either. Just getting dyno numbers back to back will be enough.

I just wanted to be clear the "same tune" for each shouldn't just be a change of the MAF values. They should correct the MAF and check the rest of the tune for improvement for each intake in order for us to really see what power gains each intake gives. The "same tune" should reflect what the tune for out of the car. I guess if you want to compare base tune files, that's fine, but I wanna see what a real dyno tune for each intake can result in. If I lived some where I didn't have to ship my car I would let it be used as a mule. Not my car so I can't say how much dyno abuse it should take.

 

[09jsw]

I already posted my unbiased dyno graph showing both being tuned back to back. I paid for the tune and both intakes. I don't sell either one and don't have any stake in this.

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