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VE vs Air Density

EFI Tuning Fundamentals

Discussion and questions related to the course EFI Tuning Fundamentals

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Hi, I just have a question regarding Air Density and Volumetric Efficiency.

I’m under the impression that Air Density and VE are two seperate things. You can have two engines with 100% VE but the air density can be different between the two. So my question is if I were tuning using a VE table at a 100% load site that value should not change based on air density correct? The IAT should compensation for density correction as the Volume stays constant? In other words if I have a site at 100% VE and the air temp drops (density increase) that number will not be any higher?

Thank You

Yes, the key is in the terminology - VE or 'volume' efficiency. The volume of air won't change but the density does based on air temperature. This is accounted for in the ideal gas law as air temperature is a variable in the equation.

I thought so, thank you!