Checked boost pressure today.

My calculations were 100% correct

Sea level pressure 1019hpa

5300 ft pressure 839hpa (this can be worked out for any altitude)

The percentage of air pressure at 5300ft compared to sea level is *

derived by 839/1019 = 0,82

I lose 18% at my altitude.

This is the ratio you must apply to the boost a pulley generates at *

sea level.

95mm pulley

6 psi x 0,82 = 4,92 psi

On my runs with the boost gauge connected, the maximum recorded boost *

was 0,33 bar = 4,78 psi

This proves my theory beautifully.

92mm pulley

7 psi x 0,82 = 5,7 psi

7,5psi x 0,82 = 6,1 psi

Based on what we saw with the 95mm pulley boosting at the bottom of *

the 6-6,5 range, I believe the 92mm will boost at 7

808E90 (Ricky) dynoed at 440HP with 4,5psi and he had full ericsson *

exhaust.

Mine dynoed at 443 HP with 4,78 psi, and i have a full akrapovic. *

Makes sense.

Therefore on a SC, power is directly proportional to amount of boost, *

regardless of altitude, making the effective delta gains compared to **

stock car, much higher at altitude