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MAP where to put?
Simon - 30/12/07 at 07:30 PM

Chaps,

Am in the process of getting all the bits and pieces into the engine bay for the Emerald, and have come to the MAP sensor.

How close to the plenum does it have to be?

Within an inch, or will on the bulkhead be fine (<18".

Cheers very much

ATB

Simon

onzarob - 30/12/07 at 07:35 PM

On an Audi Desiel the MAP sensor is half way betwwen the airbox and the header.

I suppose it the best place for an average reading of boost pressure

ps, its before the intercooler

matt_claydon - 30/12/07 at 07:42 PM

Doesn't really matter. Most people with MS have it much further than that as the MAP sensor is in the ECU.

mark chandler - 30/12/07 at 08:30 PM

XJS jag, ECU in the boot, rubber pipe all the way along the car, it does not matter in the real world.

IMHO longer would be better as it helps damp the pulses, I'm sure that some bikes even have an air reservoir where the MAP sensor sits under the throttle bodies to achieve this.

Cheers Mark

Simon - 30/12/07 at 09:35 PM

Cheers chaps

Mounted to scuttle. In a nice awkward place!

ATB

Simon

lsdweb - 30/12/07 at 11:33 PM

Hi Simon

You may not even need it with the Emerald!

You can use a TPS instead (awaiting the debate on MAP versus TPS!)

Regards

Wyn

sebastiaan - 31/12/07 at 11:13 AM

Simon's building a turbocharged engine, so TPS is not a good indicator of engine load.

On the bulhead will be fine, and basically you do not need pulsation damping if you measure MAP at a fixed crank angle every engine cycle.

lsdweb - 31/12/07 at 07:20 PM

quote:

Simon's building a turbocharged engine


I hadn't spotted that - I'll get my coat!

Simon - 1/1/08 at 02:10 AM

Got a throttle position switch (which I modified and half attached this evening - I managed to lose one of the two screws I bought today!) and the MAP sensor, along with air temp, water temp etc etc.

Wiring of loom is now mostly done, just a little tweaking, then wrap it up

Thanks for the additional input, though.

ATB

Simon

sebastiaan - 17/1/08 at 04:51 PM

Just a quick reminder: make sure the ECU is mounted such that it is not the lowest point in the system and that the connection is (if possible) pointing downwards. If you don't any condensation in the line will get into the MAP sensor, causing a great big mess when it gets below the freezing point...

MB CUSTOMS - 18/1/08 at 06:11 AM

It is not where the map sensor is mounted it is where you take the signal from that is the important bit.