How to calculate air pressure for MBCs?

[InlineFive]

Hey everyone,

I'm going to put an MBC on my Volvo 850 Turbo but I have a few questions. I know that the MBC can't reacte dynamically to air pressure changes like the stock BCS can so I need to figure out the difference in air pressure between 0-100f in Minnesota and also in other states (mainly across the East coast).

That will tell me what I should set my MBC to. I would like to set it to 11Psi (stock 10Psi, fuel maps to 15Psi) but I'm not sure how many Psi to factor for air pressure changes.

Thanks!

-Por

 

[RGUN]

Dynamic changes to pressure??? 10psi gauge will always be just that no matter what the ambient pressure is. I think you are putting to much thought into this. Unless the stock boost controller is a fairly sophisticated computer, I would have a hard time believing it actually changes anything based on absolute pressure.

Is the stock method of controlling boost not just a spring with known k value that opens under a certain pressure? If that is the case, that would open under a certain gauge pressure regardless of the absolute pressure.

 

[InlineFive]

I believe the computer adjusts the boost with the Boost Control Solenoid partly due to what it reads from the MAF/AMM.

 

[Minjin]

Just install it, set it to 11, and be done with it. Its not rocket science.

Mark

 

[RGUN]

Originally posted by: Minjin
Just install it, set it to 11, and be done with it. Its not rocket science.

Mark

Agreed.... you're talking like the potential pressure could cause catastrophic change... Atmospheric pressure is essentially 101.3kPa or 14.7 psi.... the day to day changes, or season to season is not going to be significant at all. You might see a +/- .1 psi change, but do you really think that will change anything? The answer of course is No.

 

[InlineFive]

Good to know, thanks guys.