Stock MAF vs Uprev GT MAF
12-24-2011, 06:19 AM
#21
I dont think the resistor would work. The stock Maf would still get maxed out on its side. So if ya were to try and use a resistor between the maf and ECU the maf would be maxed out at the sensor and the ECU would only see 3.5 volts(for example) and that would be the most the ECU would see.
The PMAS and GT are not exactly doubled or cut in half depending on how ya loook at it. ill give a rough idea of the comparison
1-1.5 volts very close
1.5-2 volts GT MAF scaled little higher
2-2.5 volts gt MAF scaled little higher
2.5-3 volts GT MAF scaled considerably more
3-3.5 volts GT MAF scaled considerably more
3.5 volts and above GT mare scaled very high for higher flow applications.
^^^^ that kinda give ya an idea....ill see if i can post some screen shots later after some last minute xmas shopping...
The PMAS and GT are not exactly doubled or cut in half depending on how ya loook at it. ill give a rough idea of the comparison
1-1.5 volts very close
1.5-2 volts GT MAF scaled little higher
2-2.5 volts gt MAF scaled little higher
2.5-3 volts GT MAF scaled considerably more
3-3.5 volts GT MAF scaled considerably more
3.5 volts and above GT mare scaled very high for higher flow applications.
^^^^ that kinda give ya an idea....ill see if i can post some screen shots later after some last minute xmas shopping...
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yosip1115 (12-20-2017)
12-24-2011, 09:49 AM
#22
Thanks Vince
I dont think the resistor would work. The stock Maf would still get maxed out on its side. So if ya were to try and use a resistor between the maf and ECU the maf would be maxed out at the sensor and the ECU would only see 3.5 volts(for example) and that would be the most the ECU would see.
The PMAS and GT are not exactly doubled or cut in half depending on how ya loook at it. ill give a rough idea of the comparison
1-1.5 volts very close
1.5-2 volts GT MAF scaled little higher
2-2.5 volts gt MAF scaled little higher
2.5-3 volts GT MAF scaled considerably more
3-3.5 volts GT MAF scaled considerably more
3.5 volts and above GT mare scaled very high for higher flow applications.
^^^^ that kinda give ya an idea....ill see if i can post some screen shots later after some last minute xmas shopping...
The PMAS and GT are not exactly doubled or cut in half depending on how ya loook at it. ill give a rough idea of the comparison
1-1.5 volts very close
1.5-2 volts GT MAF scaled little higher
2-2.5 volts gt MAF scaled little higher
2.5-3 volts GT MAF scaled considerably more
3-3.5 volts GT MAF scaled considerably more
3.5 volts and above GT mare scaled very high for higher flow applications.
^^^^ that kinda give ya an idea....ill see if i can post some screen shots later after some last minute xmas shopping...
12-24-2011, 10:04 AM
#23
I've logged to 5.16v, and it is at 4.8v @ 6638rpm and above. ECU has not gone into limp mode after 100+ runs to 7100rpm.... Can you explain?
Also, with my piggyback I'm modifying the MAF Signal by about -1.125v above 10PSI
Also, with my piggyback I'm modifying the MAF Signal by about -1.125v above 10PSI
They are both 5V max. The difference is that the aftermarket MAF are reprogrammed or otherwise scaled for higher flow.
For example, the stock MAF maxes out at about 400whp or so (5V) where the PMAS flows around double that before hitting 5V. I don't have hard numbers (since nobody really pushes the limits of Uprev) but I'm pretty sure someone made close to 700whp with a PMAS without maxing it out.
No idea about the flow rate of the Uprev GT MAF...it's pretty new. From what I have heard, it flows similar to the PMAS but has better idle resolution.
For example, the stock MAF maxes out at about 400whp or so (5V) where the PMAS flows around double that before hitting 5V. I don't have hard numbers (since nobody really pushes the limits of Uprev) but I'm pretty sure someone made close to 700whp with a PMAS without maxing it out.
No idea about the flow rate of the Uprev GT MAF...it's pretty new. From what I have heard, it flows similar to the PMAS but has better idle resolution.
Last edited by OldManZ350; 12-24-2011 at 10:27 AM.
12-24-2011, 03:39 PM
#25
Split Second FTC1 Fuel Timing Calibrator, not many people like it.
http://www.splitsec.com/products/datapdfs/ftc1ds~1.pdf
http://www.splitsec.com/products/datapdfs/ftc1ds~1.pdf
12-24-2011, 07:17 PM
#30
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So how do you tune or program the maf? i've been having some problems with my supercharged 350z due to the maf sensor....I just bought the PMAS HPX maf however I just installed it and the car doesn't like it...I have an AEM FIC on my car which i use for all the tuning, but this computer just has a maf clamping option... can anyone help me out a little?
thanksl
thanksl
12-25-2011, 06:05 AM
#32
That sounds about right. If you are hitting that voltage close to redline its probaly not a big deal....but when it happen at 5500 rpm...timing usually goes flat and BSF goes static....so depending on where everything is you might not notice.... but like i said before... its not good...
So how do you tune or program the maf? i've been having some problems with my supercharged 350z due to the maf sensor....I just bought the PMAS HPX maf however I just installed it and the car doesn't like it...I have an AEM FIC on my car which i use for all the tuning, but this computer just has a maf clamping option... can anyone help me out a little?
thanksl
thanksl
So does that give you output voltage or just input? the SS R4 is seeing over 5 volts but it is probaly only letting the ECU see 4.8ish....so you should be good and hence why you have never had a problem...
12-25-2011, 07:43 AM
#33
That sounds about right. If you are hitting that voltage close to redline its probaly not a big deal....but when it happen at 5500 rpm...timing usually goes flat and BSF goes static....so depending on where everything is you might not notice.... but like i said before... its not good...
12-28-2011, 06:06 AM
#34
They are both 5V max. The difference is that the aftermarket MAF are reprogrammed or otherwise scaled for higher flow.
For example, the stock MAF maxes out at about 400whp or so (5V) where the PMAS flows around double that before hitting 5V. I don't have hard numbers (since nobody really pushes the limits of Uprev) but I'm pretty sure someone made close to 700whp with a PMAS without maxing it out.
No idea about the flow rate of the Uprev GT MAF...it's pretty new. From what I have heard, it flows similar to the PMAS but has better idle resolution.
For example, the stock MAF maxes out at about 400whp or so (5V) where the PMAS flows around double that before hitting 5V. I don't have hard numbers (since nobody really pushes the limits of Uprev) but I'm pretty sure someone made close to 700whp with a PMAS without maxing it out.
No idea about the flow rate of the Uprev GT MAF...it's pretty new. From what I have heard, it flows similar to the PMAS but has better idle resolution.
12-28-2011, 09:32 AM
#35
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Correct me if I'm wrong- but looking at that earlier post it actually looks like it's simply scaled differently so that the scaling becomes more aggressive as more air is pushed through. Idle is scaled very little, while the heavier output is scaled a lot...
That made sense to me when I first saw it but is it an output / input restriction of the uprev GT? Or is it progressive (god I hate that word) scaling as you push through the power band?
That made sense to me when I first saw it but is it an output / input restriction of the uprev GT? Or is it progressive (god I hate that word) scaling as you push through the power band?
12-28-2011, 10:08 AM
#36
^^^ its both...if that makes any sense. The PMAS sensor that Z1 one talking about has a higher ceiling and is just like a factory MAF doubled. Where as the new GT MAF has better idle and cruising scaling and the the scaling widens as the airflow gets higher....
01-02-2012, 06:46 PM
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Is the Uprev GT MAF or the PMAS scaled around the same voltage as the stock MAF at idle? Wondering if it uses the entire range resolution of a 0-5 Volt scale or if it uses the 1-5 Volts like stock.
Last edited by Ngo; 01-02-2012 at 06:47 PM.
01-03-2012, 06:03 AM
#38
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I dont think the resistor would work. The stock Maf would still get maxed out on its side. So if ya were to try and use a resistor between the maf and ECU the maf would be maxed out at the sensor and the ECU would only see 3.5 volts(for example) and that would be the most the ECU would see.
The PMAS and GT are not exactly doubled or cut in half depending on how ya loook at it. ill give a rough idea of the comparison
1-1.5 volts very close
1.5-2 volts GT MAF scaled little higher
2-2.5 volts gt MAF scaled little higher
2.5-3 volts GT MAF scaled considerably more
3-3.5 volts GT MAF scaled considerably more
3.5 volts and above GT mare scaled very high for higher flow applications.
^^^^ that kinda give ya an idea....ill see if i can post some screen shots later after some last minute xmas shopping...
The PMAS and GT are not exactly doubled or cut in half depending on how ya loook at it. ill give a rough idea of the comparison
1-1.5 volts very close
1.5-2 volts GT MAF scaled little higher
2-2.5 volts gt MAF scaled little higher
2.5-3 volts GT MAF scaled considerably more
3-3.5 volts GT MAF scaled considerably more
3.5 volts and above GT mare scaled very high for higher flow applications.
^^^^ that kinda give ya an idea....ill see if i can post some screen shots later after some last minute xmas shopping...
read the thread. already covered.
01-03-2012, 09:58 AM
#40
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Just to clear up any confusion on the PMAS. Here is a link to the actual PMAS HPX NISSAN transfer function tool. Make sure you use the tube I.D. for the tube size, not the O.D. http://www.massairdirect.com/resourc.../HPXNISSAN.xls
I'm supprised this spreadsheet hasn't already been posted. DO NOT CONFUSE IT WITH THE FORD HPX SHEET!!!!
The first batch of HPX Nissan sensors had some issues at the low end of the flow range but that was resolved early on.
I'm not sure what people are talking about in reguards to resolution. The A.D.C. in the pcm is always the same. The HPX sensor will show changes as small as 2 KG/HR from .1v to 5V.
If you are looking for more resolution in the pcm you simply need to use more maf data points at the lower end of the maf range and less at the top.
Resolution has nothing to do with the actual MAF output. It has everything to do with the data points you chose to enter into the PCM.
Hopefully this helps
I'm supprised this spreadsheet hasn't already been posted. DO NOT CONFUSE IT WITH THE FORD HPX SHEET!!!!
The first batch of HPX Nissan sensors had some issues at the low end of the flow range but that was resolved early on.
I'm not sure what people are talking about in reguards to resolution. The A.D.C. in the pcm is always the same. The HPX sensor will show changes as small as 2 KG/HR from .1v to 5V.
If you are looking for more resolution in the pcm you simply need to use more maf data points at the lower end of the maf range and less at the top.
Resolution has nothing to do with the actual MAF output. It has everything to do with the data points you chose to enter into the PCM.
Hopefully this helps
Last edited by Massairdirect; 01-03-2012 at 10:01 AM.