Along the left hand side is IIc. Along the bottom is airflow.
The & curves are efficiency. The higher the efficiency, the cooler the charge.
Centering your power demand around peak efficiency is good if you plan to upgrade later on.
For a street turbo, it's not bad to run off the back of peak efficiency somewhat. It's most likely to be a smaller turbo that will spool faster & driveability will be better.
Bring oooooon the compressor maps!
Garrett/Air Research:
T3 Trim 45 - T3 Trim 50
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T3 Trim 60 - T3 Super 60
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GT20 - GT22
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GT25R - GT25-40R
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GT28RS - GT30R
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