MAP relocation
12-21-2007, 05:02 AM
#1
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MAP relocation
Has anybody moved the map sensor to the rear of the intake? Or ran it on a vacuum line and moved it under the dash? I'm deleting all the vacuum ports on the side of my intake to clean up the engine bay and running a custom setup on the back of the intake, but I still have the map sensor I would like to relocate. Any downsides to doing this?
12-21-2007, 11:46 AM
#3
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If you move the MAP sensor remote by adding a hose, you will "dampen" the readings. The longer/smaller diameter the hose, the slower the pressure changes will reach the sensor. The slower the MAP sensor responds to manifold pressure, the less accurate the ignition and fueling will be, since they are both affected by engine load, which the PCM bases on the MAP reading. The stock LT1 location is as good as it gets.
12-21-2007, 01:15 PM
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If you move the MAP sensor remote by adding a hose, you will "dampen" the readings. The longer/smaller diameter the hose, the slower the pressure changes will reach the sensor. The slower the MAP sensor responds to manifold pressure, the less accurate the ignition and fueling will be, since they are both affected by engine load, which the PCM bases on the MAP reading. The stock LT1 location is as good as it gets.
12-21-2007, 02:17 PM
#5
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Directionally, it hurts. I have no idea whether it would screw up the readings enough to hurt the way the car runs. I personally would not even consider risking the loss of accuracy for "looks". I'd choose "performance" over looks every time.... but that's just me. 
12-21-2007, 06:05 PM
#6
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why not install a hand held vaccuum guage and run it to the inside of the car. Compare the readings to the map sensor if the readings are the same I would say you would be ok with moving the map to the same length as the guage.
The differences I think would be unnoticeable.
The differences I think would be unnoticeable.
12-24-2007, 10:37 AM
#7
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Megasquirt uses an internal map sensor with a vacuum line so I think I'll be fine.
No vacuum hoses at all will be on the side of the intake, and only wires on top of the the intake will be the injectors, the iac/iat/tps will be routed underneath.
No vacuum hoses at all will be on the side of the intake, and only wires on top of the the intake will be the injectors, the iac/iat/tps will be routed underneath.
12-24-2007, 02:42 PM
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12-26-2007, 11:16 AM
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The factory LT1 MAP sensor does not use any hoses. The end of the pressure sensor nipple inserts directly into the manifold. For a remote location, obviously the hose has to be strong enough to resist deformation under full vacuum. My MoTeC ECU install manual recommends that the hose be no more than 1 meter in length, and that the sensor itself has to be located higher than the port on the manifold, in order to prevent any moisture buildup. The port on the plenum should be facing downward. No other devices should be connected to the same vacuum line as the MAP.
12-26-2007, 11:49 AM
#12
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The factory LT1 MAP sensor does not use any hoses. The end of the pressure sensor nipple inserts directly into the manifold. For a remote location, obviously the hose has to be strong enough to resist deformation under full vacuum. My MoTeC ECU install manual recommends that the hose be no more than 1 meter in length, and that the sensor itself has to be located higher than the port on the manifold, in order to prevent any moisture buildup. The port on the plenum should be facing downward. No other devices should be connected to the same vacuum line as the MAP.
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