Activation Pressure for Boost Control

[Dunc]

I did some searching on here and did not see it already talked about.

What was in the help file:
"Solenoid activation pressure sets the point where ECU starts to use the solenoid to control boost pressure. Normally this can be set a little below the minimum boost pressure in order to minimize wear on the solenoid. "

Question:
Several people I have talked to are also unsure about this. My interpretation is that the solenoid needed to see "x" amount of a boost generated from the wastegate spring before it would open up and activate (since you can't run less than the wastegate spring). Then the solenoid would take over after that and raise it to the desired pressure. However if you have a 10psi spring and an activation pressure of 15psi it wouldn't turn the solenoid on because the ecu would never see that 15psi. So if you have a 10psi spring then you would want to set it at like 8.5psi to activate. Is this correct logic?

Just wondering because when discussing with a friend he says that he has a 9psi spring and the activation pressure was 14psi.....and it did work and he controlled it up to about 17psi.

Thanks for any input guys.

[Spunkster]

Just set it to 5 psi....this is just so that you don't have the solenoid going all the time and wearing it out while cruising in vacuum.

[Dunc]

Just set it to 5 psi....this is just so that you don't have the solenoid going all the time and wearing it out while cruising in vacuum.

Will do. Would setting it at say 5 instead of 8 or something cause any variation in spooling (either slower or faster)?

[Spunkster]

depends on the pressure of your wastegate spring, but it should not affect spooling at all.