Speed Density?

[99VetteFRC]

So my plan is to use the stock MAF tune but change it to be compatible with the 2 bar MAP. The SD OS shows only a primary table. The stock tune shows 3 VE tables. So if I understand correctly, you are saying I should copy the primary VE table to my stock MAF tune and install the new MAP and it will work?

[Atomic]

You can not use the MAF with a 2bar or 3bar os.

[99VetteFRC]

How do people boost with a MAF then?

[Atomic]

Then maf can measure airflow regardless of what the pressure is. If the airflow isn't too high then the maf does its thing. People use the 2bar SD when they outflow the maf....or just prefer it instead

[99VetteFRC]

Well now I'm more confused than I was to begin with. Lets see if I got this. If I boost with a MAF then I don't need the 3BAR MAP. The MAF will tell the PCM the engine is building boost. If I make too much boost for the MAF to see then I have to switch to the 2BAR SD OS. Is this correct?

[edcmat-l1]

Well now I'm more confused than I was to begin with. Lets see if I got this. If I boost with a MAF then I don't need the 3BAR MAP. The MAF will tell the PCM the engine is building boost. If I make too much boost for the MAF to see then I have to switch to the 2BAR SD OS. Is this correct?

A MAF reports airflow, not boost. It has no idea what "pressure" is, negative or positive. Your MAP sensor reports manifold pressure. If it's a 1 bar MAP sensor, and 1 bar OS, then the sensor and computer won't recognize anything above 105 Kpa, or atmospheric pressure at sea level. A 1 bar MAP and OS are for a naturally aspirated engine which spends all it's time in vacuum (negative pressure, numerically lower than 105 Kpa).

A 2 bar MAP sensor and OS will give your computer the ability to recognize, and be able to accurate fuel the engine up to 14.7 PSI of POSITIVE pressure, or boost.

There's quite a bit more to each mode, MAF or SD, but this is the quick and dirty explanation.

[oakley6575]

So can people use a MAF with a 2 bar map/os? Or is it only used in SD?

[99VetteFRC]

A MAF reports airflow, not boost. It has no idea what "pressure" is, negative or positive. Your MAP sensor reports manifold pressure. If it's a 1 bar MAP sensor, and 1 bar OS, then the sensor and computer won't recognize anything above 105 Kpa, or atmospheric pressure at sea level. A 1 bar MAP and OS are for a naturally aspirated engine which spends all it's time in vacuum (negative pressure, numerically lower than 105 Kpa).

A 2 bar MAP sensor and OS will give your computer the ability to recognize, and be able to accurate fuel the engine up to 14.7 PSI of POSITIVE pressure, or boost.

There's quite a bit more to each mode, MAF or SD, but this is the quick and dirty explanation.

I am a mechanic and I understand how the sensors work. My question is how can I used the 2bar map sensor with the MAF OS. What do I need to change in the tuning to make it work? I thought I could just copy the the VE table fron the stock truck MAF OS and install the MAP sensor, but they are exactly the same in the stock MAF OS as it is in the SD OS from HPT. What can I do? Can't install my turbos till I get this straightened out.

[oakley6575]

Why are you so set on using the MAF?

[99VetteFRC]

I heard MAF are easier to tune... And then I have to rewire the IAT sensor... Just paid $100 for the MAF...

[Atomic]

I think SD is easier to tune, personally.

[99VetteFRC]

What IAT sensor should I use then? As mine built into the MAF.And how would I calibrate it to my PCM? Does it need to be calibrated or will it just work when I hook it up.