Perhpas I can help as I see some are having a hard time working with the software for the PCV on their Boost machine.
One question that I see a discussion on is the placement of the MAP sensor.
The charged air intake is broken down into 2 parts. 1st part is between the Turbo outlet and the throttle blade. 2nd part is between the throttle blade and the intake valve.
Place the MAP anywhere in the charged air intake you like -- But keep these facts in mind. Placing the MAP sensor at the Turbo outlet and it will read the pressure the Turbo is putting out. This is not the same pressure that is at the intake valve.
Why ?? ....... Friction loss of all the components comprising the charged air intake. Elbows/size of pipe and length/type and size of the intercooler -- -- All contribute to the loss of pressure -- Maybe as much as 2 PSI.
Place the MAP sensor between the throttle blade and the intake valve -- Now the sensor reads the true pressure/vacuum going into the cylinder -- But one then has to program for fuel delivery while in a vacuum. Not an issue if one understands this and correctly programs the software.
Personally -- I place the MAP sensor just before the throttle blade. By placing it here and data logging I can verify how much I over Boost and watch the action of the BOV. I address fueling while the charged air intake is in a vacuum in 2 tables within the software to which I'll describe later in this post.
Method of tuning for a Boosted application. I started out a few years ago with the PCV -- The PTI version hadn't been thought of then and the software wasn't quite as robust.
Being somewhat OLD and a bit brain dead (Alcohol Saturated) .. .. :rofl3: -- I couldn't comprehend fueling in a vacuum and Boost together using just one table. So -- I tuned in both TPS and Pressure. Many -- Many pitfalls tuning via this method -- But I did get pretty good tuning via this method. Even helped a few fellows out here over the years.
Then there are other terms many use. Absolute pressure - Relative pressure or atmospheric pressure -- Gauge pressure and then Kilopascal.
The software can be configured using any one of these methods or a combination of them. I can see why the user has such a difficult time with the software or if he/she thinks they have no issues -- Why their engine runs/performs poorly !!
Now -- I'll get down to programming the software that is easy for the beginner to understand.
1st is the MAP sensor. Supplied in the PTi version is a Bosch 3 BAR MAP sensor.
Three things to understand -- 1st ..... Any MAP only reads Absolute Pressure. 2nd -- The manufacturer will state the voltage and pressure operating range of their sensor. And in this case here are the values -- You don't have to understand them -- Just understand the math I'm about to show you to properly build the Voltage table. This is the table that converts the voltage sent by the MAP to a numerical value the software understands and can work with.
The operating voltage and absolute pressure range of this sensor is:
Voltage: 0.250 VDC to 4.750 VDC.
Absolute pressure: 1.59 PSI to 44.52 PSI. -- We're going to change the input to referrence pressure only - Or gauge pressure with addressing atmospheric pressure/your elevation taken into account.
It's within this table that we will change from absolute pressure to atmospheric pressure and factor in your elevation.
Here's an example of how this works -- It's really very easy to understand. At sea level the atmospheric pressure - The air pressure on your hand is 14.7 PSI (14.696 to ber exact). The sensor's low pressure value is 1.59 PSI. Here's the math -- 1.59 minus 14.7 equals a negative 13.11. (-13.11). This is what is entered for the pressure in the 1st colum. Lets say your at 1000' elevation -- Use this table to compute:
1st colum under pressure -- 1.59 minus 14.2 equals a negative 12.61 (-12.61).
2nd colum under pressure for 1000' elevation converting from absolute to atmospheric/gauge pressure:
44.52 minus 14.2 equals 30.32.
Here's a pic illustrating the voltage table converting absolute pressure to gauge pressure taking into account the atmospheric pressure at 1000'.
Only select 2 colums for this table. The software perfectly interpolates/scales to the 1000th of a volt between the low and high voltage values.
Don't understand all this -- No worries -- Just build the voltage table this exact way and providing you operate between sea level and 10,000' your Golden and will never have to come back to this table.
I don't want to loose this post so I'm letting it fly and will continue with a final posting showing how to build the Fuel pressure table taking into account both vacuum and pressure.
One question that I see a discussion on is the placement of the MAP sensor.
The charged air intake is broken down into 2 parts. 1st part is between the Turbo outlet and the throttle blade. 2nd part is between the throttle blade and the intake valve.
Place the MAP anywhere in the charged air intake you like -- But keep these facts in mind. Placing the MAP sensor at the Turbo outlet and it will read the pressure the Turbo is putting out. This is not the same pressure that is at the intake valve.
Why ?? ....... Friction loss of all the components comprising the charged air intake. Elbows/size of pipe and length/type and size of the intercooler -- -- All contribute to the loss of pressure -- Maybe as much as 2 PSI.
Place the MAP sensor between the throttle blade and the intake valve -- Now the sensor reads the true pressure/vacuum going into the cylinder -- But one then has to program for fuel delivery while in a vacuum. Not an issue if one understands this and correctly programs the software.
Personally -- I place the MAP sensor just before the throttle blade. By placing it here and data logging I can verify how much I over Boost and watch the action of the BOV. I address fueling while the charged air intake is in a vacuum in 2 tables within the software to which I'll describe later in this post.
Method of tuning for a Boosted application. I started out a few years ago with the PCV -- The PTI version hadn't been thought of then and the software wasn't quite as robust.
Being somewhat OLD and a bit brain dead (Alcohol Saturated) .. .. :rofl3: -- I couldn't comprehend fueling in a vacuum and Boost together using just one table. So -- I tuned in both TPS and Pressure. Many -- Many pitfalls tuning via this method -- But I did get pretty good tuning via this method. Even helped a few fellows out here over the years.
Then there are other terms many use. Absolute pressure - Relative pressure or atmospheric pressure -- Gauge pressure and then Kilopascal.
The software can be configured using any one of these methods or a combination of them. I can see why the user has such a difficult time with the software or if he/she thinks they have no issues -- Why their engine runs/performs poorly !!
Now -- I'll get down to programming the software that is easy for the beginner to understand.
1st is the MAP sensor. Supplied in the PTi version is a Bosch 3 BAR MAP sensor.
Three things to understand -- 1st ..... Any MAP only reads Absolute Pressure. 2nd -- The manufacturer will state the voltage and pressure operating range of their sensor. And in this case here are the values -- You don't have to understand them -- Just understand the math I'm about to show you to properly build the Voltage table. This is the table that converts the voltage sent by the MAP to a numerical value the software understands and can work with.
The operating voltage and absolute pressure range of this sensor is:
Voltage: 0.250 VDC to 4.750 VDC.
Absolute pressure: 1.59 PSI to 44.52 PSI. -- We're going to change the input to referrence pressure only - Or gauge pressure with addressing atmospheric pressure/your elevation taken into account.
It's within this table that we will change from absolute pressure to atmospheric pressure and factor in your elevation.
Here's an example of how this works -- It's really very easy to understand. At sea level the atmospheric pressure - The air pressure on your hand is 14.7 PSI (14.696 to ber exact). The sensor's low pressure value is 1.59 PSI. Here's the math -- 1.59 minus 14.7 equals a negative 13.11. (-13.11). This is what is entered for the pressure in the 1st colum. Lets say your at 1000' elevation -- Use this table to compute:
1st colum under pressure -- 1.59 minus 14.2 equals a negative 12.61 (-12.61).
2nd colum under pressure for 1000' elevation converting from absolute to atmospheric/gauge pressure:
44.52 minus 14.2 equals 30.32.
Here's a pic illustrating the voltage table converting absolute pressure to gauge pressure taking into account the atmospheric pressure at 1000'.
Only select 2 colums for this table. The software perfectly interpolates/scales to the 1000th of a volt between the low and high voltage values.
Don't understand all this -- No worries -- Just build the voltage table this exact way and providing you operate between sea level and 10,000' your Golden and will never have to come back to this table.
I don't want to loose this post so I'm letting it fly and will continue with a final posting showing how to build the Fuel pressure table taking into account both vacuum and pressure.