MAP Sensors

[pornstar]

Anyone wanna have a go at what it represents?

[Psyklops]

manifold absolute pressure...google is useful

so what do I win? new set of coilovers perhaps?

[fueltank]

lol.

[Trust-Me]

Stock MAP sensor will see just over 1bar, infact about 1700mBar.
Its a measure of pressure in the intake manifold, helps the ECU decide what fuel/ignition setting is required based on MAP vs RPM

[wynode]

Why the question?

It's a measure of pressure within the intake manifold used among other things to determine engine load.

[SIKCVC]

rather vital to your car running...

[pornstar]

im glad sum1 brought up the measurements i was going to elude to it.

mbar was the measurement u used. anyone know the conversion from mbar to hg?

[SIKCVC]

hg what? mm of HG or inches of HG???

mbar as in millibar or micro bar.

I've got some converting program... converts everything. speeds temps area wet-volume dry volume... you name it, it converts it... but i forgot where i got it from :P

[poid]

mbar = millibar

if it was microbar the prefix would be the letter "mu"

[tinkerbell]

Anyone wanna have a go at what it represents?

it simply 'represents' vacuum.

[pornstar]

ahhhhh thats better!
Tinker, vacuum u said? Can u elaborate what the importance of that is for a high revving NA engine?

[tinkerbell]

Can u elaborate what the importance of that is for a high revving NA engine?

as the pistons move down on the filling stroke the create a vacuum that draws air into the cylinder ready for the compression stroke.

the more drawing power this has the more A/F mixture that fills the cylinder and therefore the greater the combustion energy.

so vacuum is important as it determines power.

the MAP sensor compares the air pressure compared to the absolute pressure (i.e. outside air at 1 bar) and determines how much air is getting drawn into the engine and thus calculating the pulse width of the injectors to regulate the A/F ratio...

so to answer your question, it might be better to relate to a non-NA car that has a bloody big pump forcing air into the cylinders - so you see why vacuum is important for NA cars - as it is the only thing that fills the cylinders with A/F mixture...