Snypa

Im turboing a 250cc kawi, but thats not important.

I would like to run 4psi for cassual ridding and 8-14psi when I want to ride hard.
For this I will get the TURBOSMART Dual Stage MBC........BUT........

The wastegate spring is default @ 7psi, does this mean I would never be below 7psi?

I'm having a head-scratcher thinking about controlling the boost in that^ way if the wastegate will not release under 7psi.

-OR-

Would the setup likely only come out to around 4psi anyway due to plumbing and the intake plenum tank?
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Are there any boost controllers for the COLD(intake) side that would allow me to do this? Like a controlable BOV?

Im sure I will have more questions, but this one has me stumpped

brettsb16a2

It won't start opening until about 7. I have a 9psi spring and i get as high as 10.2 psi boost sometimes. If your set up is right you will get 7psi or higher.

Snypa

So I understand that the TURBOSMART Dual Stage MBC can allow it to remain shut. But I wish it could also open it sooner, stupid spring.(I understand why it can't)

So let me throw this out there, maybe I shouldnt.
Could I run a second, smaller wastegate, someplace on the intake side? Maybe next to the BOV and put a 4psi spring in it? I say to use a wastegate, because I have yet to find a controllable bov, that works like the WG does with the turbosmart MBC.

Does that ^ sound dumb? or way out there?

herman

Or just get a 4 psi wastegate