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a stand alone engine management system.... at least i think so.
 

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Originally posted by 1turbofocus:
My question would be why would you want to

tom
<font size="2" face="Verdana, Arial">I got this one FocusInterceptor!

Tom: He has already determined the "Why" or he wouldn't ask "What would it take".

So like the man asked people! What would it take?
 

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Tom is just trying to get a feel for what application someone could possibly want to swap a MAF based system into a MAP. Most tuners that have MAP systems would love to change to a MAF for better A/F ratio across the entire power band, especially if the car has forced induction.
 

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Originally posted by Seawolf:
Most tuners that have MAP systems would love to change to a MAF for better A/F ratio across the entire power band, especially if the car has forced induction.
<font size="2" face="Verdana, Arial">Actually, most tuners who HAVE a map sensor don't CHANGE but ADD a MAF sensor.

A MAP sensor determines engine load by comparing it to readings from a barometric(ambient atmospheric pressure) sensor, in general, a high manifold pressure indicates the engine is under load. With a MAF sensor the computer is *told* how much air is entering the engine by the MAF sensor's changing output.

Having a MAP sensor makes turbo charging applications less painfull(Can't make it worse!).

Alot of cars 1990+ are equipped with MAP sensors still, though a mechanic will refer to the item in question as a "barometric pressure sensor" or "BP sensor", it is used only to measure atmospheric pressure, and an MAF
sensor is used to detect engine load.



[ 09-17-2002, 10:32 AM: Message edited by: 2001ZTSTypeXASpec ]
 

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It would take something like this:
http://sandstallion.com/link_afm.html

MAP sensors are actually a bit better for forced induction systems than a MAF for a couple reasons.
Since it's taking the air pressure/temp that is actually in the intake manifold it's more accturate than the MAF which is at the beginning of the intake tract before it has been compressed and heated by the turbo/supercharger (and then cooled by intercooler is so equipped). This can be several feet of intake plumming that all this air has to move through after the air mass has been measured.

With a MAP system you can do away with your entire intake plumming. You could put an airfilter right on the throttle body. So, Near zero intake restrictions. Ususally it's just a big fat intake tube plumbed somewhere to get cooler air.

You can not max out the flow of a MAP system, since it doesn't measure that. MAF's have a rating in what the max CFM they can measure is and as you get more HP out of your engine you can run into limits of the MAF. The MAP sensor is limited by pressure, not flow. They are usually measured in BAR (1 BAR = ~14.7PSI) so as long as the boost pressure doesn't exceed the rated pressure your fine. Usually improvements that help the engine breathe air reduce the pressure while increaseing the flow so it goes hand and hand with the MAP systems.

And lastly, for turbo guys, with a MAP system you can use a blow-off valve that vents to the atmosphere for that Psssst sound when letting off the gas. With a MAF system this is metered air getting vented so it makes the engine run very very rich when letting off the gas to shift. Makes the engine bog and sometimes causes it to die when returning to idle.

On the negative side MAP systems are a bit harder to get decent idle and emissions control at low RPMs.
 

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Originally posted by Seattle944t:
On the negative side MAP systems are a bit harder to get decent idle and emissions control at low RPMs.
<font size="2" face="Verdana, Arial">Which is why you'd want to keep the MAF type setup, this way they could work in conjunction with each other.

...

Or you could fake it, which is what US FOCUS OWNERS CAN DO. There is some R&D going on right now, and uses it's own supplied MAP and Air Temp sensors (speed density) to fake the MAF signal into the ecu. This allows you to remove the MAF sensor all together (and vent the bov to atmosphere) and have some control over a/f ratio.

...

But I won't bore you anymore with that, onto the original question...

What would it take to go from a MAF setup like w have now to a MAP setup?
<font size="2" face="Verdana, Arial">
 

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Did you even look at the link I posted? That is EXACTLY what the AFM link is made to do. You keep the factory ECU but change from a MAF to a MAP sensor. The AFM link is tuned to give voltage to fool the ECU into thinking it's getting the MAF data. You can modify the voltage table, thus adjusting fuel (+/-80% I believe), in 500 RPM increments.
 
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