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having fun
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Discussion Starter #1
ok please end this debate--were converting a 4 cyl 91 stang to v8,i ran the wire harness tonight for the mass air,buddy of mine im building this car with INSISTS the car can be made to run speed density-by reattaching a vacuum line to the old map sensor and just not running a meter-using the a9p ecm i just put in from his 88


ive been doing this long enough to assume the likely-that the car will run like dogshit and throw codes without a sensor-if it runs at all--i already have a stock meter aside knowing itll probobly be used

ok guys fire away!!
 

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Unless you use an e-prom programmer and change the data to read the BAP instead of the MAP, you can't do it.

You CAN modify an A9L to run Speed Density, but you need the programmer and need to know what you are looking at.

A stock A9P will not run without a Mass Air
 

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having fun
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Discussion Starter #7
Unless you use an e-prom programmer and change the data to read the BAP instead of the MAP, you can't do it.

You CAN modify an A9L to run Speed Density, but you need the programmer and need to know what you are looking at.

A stock A9P will not run without a Mass Air
yes or i can repin the harness also and use a speed density ecm-basically converting the harness to speed density

its fine-he will see it needs a sensor to run
 

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I can end this debate conclusively.

When the MAF voltage goes out of range, but the TPS input is still valid, the PCM uses a table indexed by RPM and throttle position to determine fuel requirement, effectively making it N-Alpha.

In the event both the TPS and MAF are determined to be invalid, it uses a function of RPM only to determine fueling.

The MAP sensor on that PCM is used as a barometric pressure sensor, and the only significant function it is used for is determining which spark table to run at part throttle.

It is possible to calibrate the N-Alpha table and operate the engine without the MAF sensor, but this is very time consuming.

Brian
EFI-Unlimited
 

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He is not anyone I would want working on or standing near me when Im working on my junk.
 

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having fun
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Discussion Starter #13
Probably has a killer "B" cam he wants to run as well....

has a stock h.o cam i pulled out of storage-its actually a 85 thunderbird shortblock-we put a built motor in a friends bird and transfered his old shit to a dead 4 cyl stang
 

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I have a SD computer if you need it. But you should save your friend from hisself and insist that he run the A9L and a MAF.
 

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having fun
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Discussion Starter #15
I have a SD computer if you need it. But you should save your friend from hisself and insist that he run the A9L and a MAF.


i put the a9p in it already-gonna go back to the shop tonight and put the rest of the intake on...and yes i can see why it would posibly run...but who would want to drive it like that
 

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having fun
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Discussion Starter #17
You are gonna have to "re-pin" the ecm connector to use it.

yeah im aware,gotta basically un-convert from mass air



just undo whats done in a mass air conversion--but still not worth my time


when i install a perfectly good harness,and an ecm and some jackass wants to add work to my project i let em


then i go,fix the errors and steal that customer all for myself down the road

im doing this guy a favor and wiring this car-yes im being paid but its not my actual project-YET!!


the kid that owns the car already knows once its out of this garage im gonna be doing the work on it from here on in-he just didnt meet me till this project was started
 
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