Compressor Map

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The compressor map page allows you to plot engine operating conditions on a map of compressor efficiency. There are two purposes for doing this:

1. To select a compressor that will have the highest efficiency at various operating conditions, such as the maximum torque, the wastegate opening point (the point where maximum boost is reached), and the maximum rpm (engine redline), and
2. To ensure that the compressor does not operate beyond its surge limit.

The following inputs are used to determine the pressure ratio and air flow rate, which are plotted on the compressor map

Displacement – if you are using two turbochargers, enter 1/2 of your engine displacement.

Efficiency

Engine speed

Maximum RPM

Boost pressure

Maximum boost

Intake air temperature

Intercooler pressure drop

Engine stroke

Select map – use this drop-down list to select from the available compressor maps. Tip: you may find it easier to use the compressor maps page to select a compressor map.

The compressor map image can be zoomed using two fingers. A long press with one finger will reset the zoom.

On the compressor map image, a red dot shows the point based on your inputs.

Green lines illustrate all pressure ratios for every 1000 RPM up to the maximum RPM or redline.

A blue line illustrating all pressure ratios at the specified RPM.

A magenta line illustrates all points along the boost curve.

A brown dot and brown lines show your touch point, so you can associate a location on the image with values on the scales.

The compressor map calculation also utilizes the barometric pressure input from the conditions page.

In addition to the compressor map diagram, this calculation also displays the numeric pressure ratio and air flow rate, the values which are plotted on the compressor map.