MAF to MAP conversion
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morgie
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MAF to MAP conversion
Is it something that could be done without having to change for an Aftermarket ECU ?
morgie
'98 4Runner V6 Manual 4x4.
'98 4Runner V6 Manual 4x4.
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boostjunkie
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vrg3
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Never say never, boostjunkie. :)
I don't think there's anything out there that can do it off the shelf, but I've always secretly wanted to try. Basically an airflow signal is fairly similar to manifold pressure times engine speed, with a correction factor for temperature.
If you shorten the vacuum line going to the stock MAP sensor you could probably use it and just add an intake air temperature sensor.
Basically, I was thinking I'd install an IAT sensor and do some data logs of voltage readings from the MAF sensor vs. readings from the MAP and IAT sensors and a frequency-to-voltage converter reading off the tach signal. Then I'd try to fit some curves to the data and encode the function as an analog circuit. If the data wasn't well behaved I'd resort to a lookup table in a microcontroller, but I like analog circuits.
The neat part about this would be that it could be tested and developed without modifying the car.
Even after it were complete, you wouldn't have exactly the same signal, but it would probably be close enough for the self-learning ECU to figure out the rest.
I don't think there's anything out there that can do it off the shelf, but I've always secretly wanted to try. Basically an airflow signal is fairly similar to manifold pressure times engine speed, with a correction factor for temperature.
If you shorten the vacuum line going to the stock MAP sensor you could probably use it and just add an intake air temperature sensor.
Basically, I was thinking I'd install an IAT sensor and do some data logs of voltage readings from the MAF sensor vs. readings from the MAP and IAT sensors and a frequency-to-voltage converter reading off the tach signal. Then I'd try to fit some curves to the data and encode the function as an analog circuit. If the data wasn't well behaved I'd resort to a lookup table in a microcontroller, but I like analog circuits.
The neat part about this would be that it could be tested and developed without modifying the car.
Even after it were complete, you wouldn't have exactly the same signal, but it would probably be close enough for the self-learning ECU to figure out the rest.
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boostjunkie
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JasonGrahn
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Using it on my FD and I love it. They produce the ECU in Austalia and have all Subaru applications. I was thinking of eventually getting one for the Legacy.JasonGrahn wrote:rogue, you keep talking about the microtech. Have you personally used it before?
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vrg3
- Vikash
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That looks similar in concept to what I was describing, except it isn't meant to simulate the MAF signal precisely. Rather, it gets pretty close and lets you manually tune it the rest of the way. In one sense, it's easier for them to build. In another sense, they can sell it as a MAF-to-MAP kit with a built-in AFC kind of thing.