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Discussion Starter #1
I found my old GM 3bar MAP sensor from my supercharged mustang and I would like to put it on the foxbody with the Pro-M. I am assuming that I need to turn this MAP sensor on in the calibration tables.

Is Calibration: Sensors: MAP: Configuration: Map_HP the correct place to turn this on?
 

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I have a very old strategy but to answer your question, YES your are correct. Pullup the MAP gauge from Variables and make sure vacuum numbers are correct on the gauge when the car is running. Or you can hookup a vacuum/boost pump to the MAP sensor's vacuum line to make sure it's reading correctly with either vacuum or boost (do this with the vehicle NOT running KOEO).

I hope this helps
Michael Plummer
 

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Discussion Starter #3
Thanks.
This worked. I turned it on in the the, wrote the tune to the Pro-M, keyed on the car and saw 29.999 inHg.
Started the car up and saw 17inHg on the MAP which confirms the 12inHg on the mechanical vacuum gauge.

This also explains why my brake pedal is rock hard. hahahaha
Guess I will add a reservoir to see if that helps the brake situation before going hydroboost.
 

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I added one too just because I think it's a nice variable to be able to log. I agree with Chris that the number is irrelevant to power but I wanted to monitor it before and after meth and for the cost of the sensor it was a no brainer.
 

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Thanks.
This worked. I turned it on in the the, wrote the tune to the Pro-M, keyed on the car and saw 29.999 inHg.
Started the car up and saw 17inHg on the MAP which confirms the 12inHg on the mechanical vacuum gauge.

This also explains why my brake pedal is rock hard. hahahaha
Guess I will add a reservoir to see if that helps the brake situation before going hydroboost.
Can I change that my map sensor will read in psi not in inHg? or do I have to convert it to see how much boost I make in psi. My car should be around 26 psi at WOT so by looking at the map gauge should I see around 53.864 inHg ?
 

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Under sensors, Map, drag boost to the scope window. It will measure in psi.
 

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I was thinking to at knock sensor is it possible with Pro M system ?
I am not aware of any knock sensor functionality unless your car originally came with them (newer models), then it may be a feature. As far as with the foxbody platform, I have seen a lot of issues with false detection of knock and other issues.
It would be a nice feature to have, if it was dependable.
 

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Check out J&S Safeguard for knock detection. One of these days I'm going to integrate their Interceptor or Vampire into my system.
 

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I am not aware of any knock sensor functionality unless your car originally came with them (newer models), then it may be a feature. As far as with the foxbody platform, I have seen a lot of issues with false detection of knock and other issues.
It would be a nice feature to have, if it was dependable.
I have a 97 mustang Gt With cobra engine block and there is place to install knock sensor I just wish it would be possible to connect this to pro m System
 

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Under sensors, Map, drag boost to the scope window. It will measure in psi.
Thanks.
This worked. I turned it on in the the, wrote the tune to the Pro-M, keyed on the car and saw 29.999 inHg.
Started the car up and saw 17inHg on the MAP which confirms the 12inHg on the mechanical vacuum gauge.

This also explains why my brake pedal is rock hard. hahahaha
Guess I will add a reservoir to see if that helps the brake situation before going hydroboost.
why there is difference in the reading on those? 17inHg and 12inHg shouldn’t they read the same ? Please explain
 

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why there is difference in the reading on those? 17inHg and 12inHg shouldn’t they read the same ? Please explain
A mechanical boost gauge will be zeroed for atmospheric pressure. MAP is absolute pressure. 14.7 psi on MAP is 0 on a traditional boost gauge. If you read "boost" from Pro-M's variables, it will convert the MAP reading to a traditional boost gauge reading for you by zeroing atmospheric. However, it will be psi on both sides of 0 where something like an autometer gauge will use inHg for below atmospheric and psi for above. 2 inHg is ROUGHLY -1 psi. If you see -7 psi on the Pro-M boost variable, that's about 14 inHg vacuum on a traditional gauge.

I'm not sure I'm really explaining why 17inHg confirms 12inHg though...
 

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Discussion Starter #17
The MAP sensor reads absolute.
Without the car running the sensor should read atmospheric pressure whichever at sea level is equal to 30inHg.
As the manifold pulls vacuum it reduces the pressure on the sensor.
Pulling 12inHg on a standard vacuum gauge that reads 0 at atmospheric conditions should read 18inHg on the MAP sensor.
30-12=18. Maybe the 17 is what was misleading everybody.
 

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The MAP sensor reads absolute.
Without the car running the sensor should read atmospheric pressure whichever at sea level is equal to 30inHg.
As the manifold pulls vacuum it reduces the pressure on the sensor.
Pulling 12inHg on a standard vacuum gauge that reads 0 at atmospheric conditions should read 18inHg on the MAP sensor.
30-12=18. Maybe the 17 is what was misleading everybody.
Well said.
 

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A mechanical boost gauge will be zeroed for atmospheric pressure. MAP is absolute pressure. 14.7 psi on MAP is 0 on a traditional boost gauge. If you read "boost" from Pro-M's variables, it will convert the MAP reading to a traditional boost gauge reading for you by zeroing atmospheric. However, it will be psi on both sides of 0 where something like an autometer gauge will use inHg for below atmospheric and psi for above. 2 inHg is ROUGHLY -1 psi. If you see -7 psi on the Pro-M boost variable, that's about 14 inHg vacuum on a traditional gauge.

I'm not sure I'm really explaining why 17inHg confirms 12inHg though...
Makes sense now thanks for explaining
 
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