Markus1981

Hi Guys

I read a couple of threads on how to calibrate the Stock MAP Sensor for the power fc (which is what i have in my car ) .
I want to start learning to tune the car , but want to make shure the basics are right .

So from what i understand from reading threads about the issue :

The MAP Sensor measures Absolute Pressure and i can only change the scale of the sensor and offset
Athmospheric pressure at sea Level is 760 mmhg
Athmospheric pressure at 1400 m is 648 mmhg

The power FC deducts 760 mmhg from the absolute pressure to calculate the boost pressure .

I am in Pretoria which is 1400 m above Sea Level

I had a look at my and my friends car ,and our intake pressure readings on the commander with ignition on , engine off on both cars are -124 and -140 mmhg respectively .
On Sea level this should obviously be 0 right ?
if my understanding is right a perfectly calibrated sensor would show 112 mmhg
(Sea level athmospheric pressure - altitude athmospheric pressure ==> 760 - 648 = 112)


This means in turn , that if i have boost adjusted in the power fc settings to 0.8 kg/cm2 (588 mmhg) i am boosting really 588mmhg + 124 mmhg ?
Therefore overboosting .


What is the best way to go about this problem ?
Can i somehow tell the power fc that i am on altitude ?

I want to start to tune the car myself ( as there are no people that want to touch a power fc in my area )
I will use the a Innovate LC with a FC Hako and tune AFR as described in the manual on innovates website .



Can someone please tell me if i understand this correct and give me hints how to go about this ?


my current mods :

Power FC & Oled commander with FC Hako
Stock Twins
HKS RS twin intakes
Stock motor
Blitz Catback
Stock Cat ( finally found one to put back in before i start tuning )
Thermostat mod
Blitz BOV
Superpro enhancement kit

Mods on their way :
Greddy type LS FMIC
Greddy compression tube
Koyorad N-FLO Radiator
Oehlins Coilovers

Markus1981

Unfortunately can't edit anymore . I meant a perfect calibrated sensor should read - 112 mmHg not 112