Do you need a MAT if using MAF?
Moderators: jsmcortina, muythaibxr
-
- Helpful MS/Extra'er
- Posts: 139
- Joined: Sat Dec 04, 2010 1:49 am
- Location: Melbourne, Australia
- Contact:
Do you need a MAT if using MAF?
Hope this is the right forum... Do you need a MAT if using a MAF, as I gather the MAF calculates the Mass Airflow based on temp, so is self correcting. My MAF (Bosch HFM5) also provides a seperate temp sensor, if I do require a MAT.
Jim
Jim
1968 Australian Morris Mini fitted with a 1310cc A+ engine
14point7 WB, TunerStudio MS Ultra & MegaLogViewer HD
My Blog: http://www.jims-blog.com
14point7 WB, TunerStudio MS Ultra & MegaLogViewer HD
My Blog: http://www.jims-blog.com
-
- Super MS/Extra'er
- Posts: 17507
- Joined: Thu Apr 16, 2009 8:08 pm
Re: Do you need a MAT if using MAF?
While you can run without it, adding a MAT sensor will allow a couple extra features like MAT timing retard. Plus it's handy to data log.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
-
- Helpful MS/Extra'er
- Posts: 139
- Joined: Sat Dec 04, 2010 1:49 am
- Location: Melbourne, Australia
- Contact:
Re: Do you need a MAT if using MAF?
Thanks Matt. I'll connect up the MAT temp sensor then... it will be the most accurate.Matt Cramer wrote:While you can run without it, adding a MAT sensor will allow a couple extra features like MAT timing retard. Plus it's handy to data log.
1968 Australian Morris Mini fitted with a 1310cc A+ engine
14point7 WB, TunerStudio MS Ultra & MegaLogViewer HD
My Blog: http://www.jims-blog.com
14point7 WB, TunerStudio MS Ultra & MegaLogViewer HD
My Blog: http://www.jims-blog.com
Re: Do you need a MAT if using MAF?
HFM5 brother! I am just installing one of these now.Matt Cramer wrote:While you can run without it, adding a MAT sensor will allow a couple extra features like MAT timing retard. Plus it's handy to data log.
Matts suggestion would only work in a blow through turbo setup. Most factory setups (At least Subaru) put the maf pre turbo.
But to answer your question. Yes hookup the MAT. Theoretically the MAF should compensate but realistically even OEM use MAT.
Tuning the curve will be different since the MAF will compensate somewhat but usually not enough. You will have to do lots of data logging in cold/hot days to figure out the true curve. I would start with a very mild or no curve and work from there.
-
- Super MS/Extra'er
- Posts: 884
- Joined: Sat Apr 30, 2011 12:34 pm
- Location: Sandefjord, Norway
Re: Do you need a MAT if using MAF?
I think I can set up a scatter plot to find that function, will have to think a little bit about it. The curve should hopefully be the same for all HFM5s, so it is just a matter of finding it.
The HFM5 is a very user friendly piece of kit, as long as you stay away from oiled air filters and MAF cleaning concoctions they are accurate and reliable.
The HFM5 is a very user friendly piece of kit, as long as you stay away from oiled air filters and MAF cleaning concoctions they are accurate and reliable.
Joachim
1974 Jensen-Healey
1990 VW Caravelle Syncro - running MS3+X
2014 Ford Fiesta EcoBoost
1974 Jensen-Healey
1990 VW Caravelle Syncro - running MS3+X
2014 Ford Fiesta EcoBoost
-
- Helpful MS/Extra'er
- Posts: 139
- Joined: Sat Dec 04, 2010 1:49 am
- Location: Melbourne, Australia
- Contact:
Re: Do you need a MAT if using MAF?
Thanks... I'm using a new Bosch MAF 0 280 217 123 as fitted to Opel Corsa SB 1.4l SPI engines, also known here in Australia as the Holden Barina. My engine is a Rover Mini A+ 1310cc unit. It's a new unit. So I'll connect up it's temp sensor (Pin 1) instead of the GM MAT sensor I previously used in my SD setup as this would be a lot easier fabrication wise. I'll keep you posted.jacky4566 wrote:HFM5 brother! I am just installing one of these now.Matt Cramer wrote:While you can run without it, adding a MAT sensor will allow a couple extra features like MAT timing retard. Plus it's handy to data log.
Matts suggestion would only work in a blow through turbo setup. Most factory setups (At least Subaru) put the maf pre turbo.
But to answer your question. Yes hookup the MAT. Theoretically the MAF should compensate but realistically even OEM use MAT.
Tuning the curve will be different since the MAF will compensate somewhat but usually not enough. You will have to do lots of data logging in cold/hot days to figure out the true curve. I would start with a very mild or no curve and work from there.
1968 Australian Morris Mini fitted with a 1310cc A+ engine
14point7 WB, TunerStudio MS Ultra & MegaLogViewer HD
My Blog: http://www.jims-blog.com
14point7 WB, TunerStudio MS Ultra & MegaLogViewer HD
My Blog: http://www.jims-blog.com
-
- Helpful MS/Extra'er
- Posts: 139
- Joined: Sat Dec 04, 2010 1:49 am
- Location: Melbourne, Australia
- Contact:
Re: Do you need a MAT if using MAF?
Thanks for your reply... couple of Q'ssubwoofer wrote:I think I can set up a scatter plot to find that function, will have to think a little bit about it. The curve should hopefully be the same for all HFM5s, so it is just a matter of finding it.
The HFM5 is a very user friendly piece of kit, as long as you stay away from oiled air filters and MAF cleaning concoctions they are accurate and reliable.
Are you talking about the temp-resistance of the Bosch MAF... if so this is it.
Code: Select all
Temperature-dependence R= f() of the temperature sensor
C -40 -30 -20 -10 0 10 20 30 40
k 39.26 22.96 13.85 8.609 5.499 3.604 2.420 1.662 1.166
C 50 60 70 80 90 100 110 120 130
r 835 609 452 340 261 202 159 127 102
I guess the oil may contaminate the hot film sensor? I guess just a plain paper filter pod will do?
1968 Australian Morris Mini fitted with a 1310cc A+ engine
14point7 WB, TunerStudio MS Ultra & MegaLogViewer HD
My Blog: http://www.jims-blog.com
14point7 WB, TunerStudio MS Ultra & MegaLogViewer HD
My Blog: http://www.jims-blog.com
-
- Super MS/Extra'er
- Posts: 2221
- Joined: Tue May 04, 2004 8:20 pm
- Location: St Louis
- Contact:
Re: Do you need a MAT if using MAF?
I always mount a IAT, even if all I do is mount it very close to the air filter. That bit of info can be huge to figure out if the motor is sucking in extremely hot air.
Andy
Andy
-
- Helpful MS/Extra'er
- Posts: 139
- Joined: Sat Dec 04, 2010 1:49 am
- Location: Melbourne, Australia
- Contact:
Re: Do you need a MAT if using MAF?
Thanks Andy.. I wan't to use the seperate temp sensor that is built-in to the MAF, so I don't have to mount more a seperate IAT sensor. The temp sensor inside the MAF is not used by the MAF, it's there for end user use only. It' very convenient as it's measuring at the same physical location where the MAF sensor is also measuring.whittlebeast wrote:I always mount a IAT, even if all I do is mount it very close to the air filter. That bit of info can be huge to figure out if the motor is sucking in extremely hot air.
Andy
Jim
1968 Australian Morris Mini fitted with a 1310cc A+ engine
14point7 WB, TunerStudio MS Ultra & MegaLogViewer HD
My Blog: http://www.jims-blog.com
14point7 WB, TunerStudio MS Ultra & MegaLogViewer HD
My Blog: http://www.jims-blog.com
Re: Do you need a MAT if using MAF?
Bump.
Was anyone able to find an OEM Correction table? Since this maf seems common in VW/ Opel/ Vauxhaul I'd like to know if they are using it as a scalar. Maybe they only use the internal MAT for emergencies/ overheating.
I am not familiar with VW. Is there any open source tuning software i could dig around with?
Was anyone able to find an OEM Correction table? Since this maf seems common in VW/ Opel/ Vauxhaul I'd like to know if they are using it as a scalar. Maybe they only use the internal MAT for emergencies/ overheating.
I am not familiar with VW. Is there any open source tuning software i could dig around with?