I did searches and have read people saying that a boost contoller can't lower boost, only raise it.
And now I am confused

Theoretical:

OK, . I have a boost controller and sometimes I want to run 8psi and sometimes 12psi(such as an APEXI ACV with Hi and Lo settings). If the wastegate is big enough to let enough gas out to lower it to 8 psi then why wouldn't it work?

I think I understand the concept: You can't lower boost if the wastegate can't escape enough gas to lower the boost to that level. Thus, giving you a limit to how much boost can be lowered based of the effectiveness of the wastegate.

So, If I have a big wastegate, why can't I lower boost from 12psi to 8psi?
or does all of this just pertain to the stock wastegate which is barely adequate?

Tanks guys(and the few gals)

 

I know you know.....

 

you can't lower it any lower then what the turbo runs with no boost controler. if your controler is set at 12, then sure you can lower it. but if you're running 12 with no boost controler (easy to do with exhaust and intake) then adding a boost controler won't/can't lower it.

 

Ok, so maybe I'm missing how the wastegate works. I understand, kind of. I think I just need to do some research.

Thanks

 

From what i know, say you have an external wastegate with a 7psi springs and say you have an electronic boost controller, when you have the boost controller off your turbo will only boost the minimum 7psi..You cannot lower the boost to below 7psi..But you can raise the boost to 7 psi above!