Boost Solenoid?

[Kenna802]

Hi there can anyone tell me how a boost solenoid on a gtst 97 skyline holds the boost low ( 5 psi ) untill 4500rpm than allows it to go to 7 psi. I know that the solenoid closes and grounds it but what allows it decide what boost it has? If you replace the boost solenoid with a turbo tech controller you can get what ever boost u decide ( untill r & r kicks in )

I was just wondering if there is some restiction in the vac line or something like that to hold it at 5 and 7 psi. would the factory waste gate have something to do with it? Sorry to waste peoples time if this an easy one. Cheers all

[lachlanw]

the waste gate spring pressure is 5 psi . so you get 5 psi . the solenoid is "T"d into the pressure line to the waste gate . in the hose to the solenoid is a restristor. when the solenoid opens it leaks pressure out of the line so the waste gate spring only "see's" 5 psi when there is actually 7-8 in the pipe

you dont replace the solenoid with the manual boost controller . you remove the T piece in the line and put the manual controller in its place

[Kenna802]

Ok I know that the boost controller goes in lew of the T piece. But the solenoid becomes obsolete. ( removed ) What is the vac line on the top of the solenoid do? ( the one that get plugged up) I can understand about the restrictor but if we just removed it wouldn't we get a higher boost with the right calculations on restrictions and a heavier waste gate spring? Than we could keep the existing solenoid with higher boost applications

Dont get too annoyed I jus wanna learn!

Edited January 20, 2010 by Kenna802