How the DME calculates load, i.e. the Transfer Function

Talk and Tech about turbocharged 924/944/968 cars
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johnb
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If anyone knows of a reasonably cheap MAF sensor with a known output curve that I could use for this, please let me know. I could make it work with any MAF because all I need is the voltage output, but it would be better if I had the actual curve so that I will know the mass actual air flow too.

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Dare
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johnb wrote: Sun Nov 30, 2025 6:43 am If anyone knows of a reasonably cheap MAF sensor with a known output curve that I could use for this, please let me know. I could make it work with any MAF because all I need is the voltage output, but it would be better if I had the actual curve so that I will know the mass actual air flow too.
I can't vouch for the accuracy, but this page purports to give the transfer functions for a variety of different MAFs: http://efidynotuning.com/ (select MAF > MAF Transfers).

The 90mm MAF from a Ford Lightning or Cobra (p/n 1L3F-12B579-AB) seems to a popular choice of modders across a variety of cars.

This place offers a replacement Ford MAF that comes pre-calibrated: https://pmas-maf.com/product/mh90-1l3f- ... placement/. I believe they also can provide the measured transfer function. However this option may not qualify as reasonably cheap.
Jay
2012 Porsche Cayman R
1986 Porsche 944 Turbo

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johnb
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Dare wrote: Mon Dec 01, 2025 8:17 am
johnb wrote: Sun Nov 30, 2025 6:43 am If anyone knows of a reasonably cheap MAF sensor with a known output curve that I could use for this, please let me know. I could make it work with any MAF because all I need is the voltage output, but it would be better if I had the actual curve so that I will know the mass actual air flow too.
I can't vouch for the accuracy, but this page purports to give the transfer functions for a variety of different MAFs: http://efidynotuning.com/ (select MAF > MAF Transfers).

The 90mm MAF from a Ford Lightning or Cobra (p/n 1L3F-12B579-AB) seems to a popular choice of modders across a variety of cars.

This place offers a replacement Ford MAF that comes pre-calibrated: https://pmas-maf.com/product/mh90-1l3f- ... placement/. I believe they also can provide the measured transfer function. However this option may not qualify as reasonably cheap.
Thanks, funnily enough I had just emailed them earlier today to confirm that it comes with the data, since they hint at that but it's not 100% clear. I think this might be the best option. There are cheaper MAFs out there on places like Amazon but I would be hesitant to trust them, even if I could find data for them which is unlikely.

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