Equations..

[Jim Staff]

   I need help with equations for a MAP system. I have this general equation..

        PV=nRTe
           P = pressure [assuming intake from MAP sensor] in KPA
           V = Displacement of Cylinder                   in Liters
           N = moles of atmosphere                        in Moles
           R = Universal gas constant : 8.31L/Kpa         W/ KPA & Liters
           T = Absolute temp ¡K of intake air [temp sensors job]
           
           Could you help me nail down the real units on these things? I'm a 
second year chemistry student, and I know this simple Gas law but I don't know 
the units in this Application!!!

           e = Volumetric Efficiency                      Unitless
           
           Could someone provide a formula to just get a cheap estimate of this 
term. I can't solve for it since I have no empirical data, also no staight 
substitutions work either: as the e terms will cancel. 

           I have a briggs and stratton engine, and those bastards won't give me
volumetric efficiency information at all. They said that it wasn't even 
availible. I said bullshit if the didn't know Ve they wouldn't know other 
general things like fuel consumption and torque. I even said I didn't care if 
the values weren't worth shit.


            Please help me, I'm a High school hobbiest. I have no access to high
tech equipment like dyno's and bench equipment. My life sucks,
      
 
            Thanks for your concern,
                   Jim Staff