[arkansasfiddler]

have acquired a turbonetics vbc controller for my 87 grand national but have no instructions. controller has 4 ports . there is an arrow pointing away from one port. my wastegate has but one hose. have seen the inst. for hooking it up to a dual port wastegate but not for my application. i am assuming the port with the arrow goes to the wastegate and the one opposite would go to the boost source, do i plug the other two ports? seems it would have to bleed from somewhere.

[Robert]

Originally Posted by arkansasfiddler

have acquired a turbonetics vbc controller for my 87 grand national but have no instructions. controller has 4 ports . there is an arrow pointing away from one port. my wastegate has but one hose. have seen the inst. for hooking it up to a dual port wastegate but not for my application. i am assuming the port with the arrow goes to the wastegate and the one opposite would go to the boost source, do i plug the other two ports? seems it would have to bleed from somewhere.

Heres the MBC install instructions:
http://turboneticsownersclub.com/turbos/mbcinstall.pdf

[59Ram]

Will connecting the controller in the fashion as shown in the manual limit the boost from 0 to the spring rate in the wastegate or other. ie. With a 5psi spring in a Racegate do you obtain 0 to 5psi boost range. And does turning the valve all the way in produce 0 or 5psi? The other variable is the "screw" adjustment, spring tension on the wastegate, does the screw turned all the way in produce 5psi (w/ 5psi spring) and all the way out produce 0psi boost.

[Robert]

Originally Posted by 59Ram

Will connecting the controller in the fashion as shown in the manual limit the boost from 0 to the spring rate in the wastegate or other. ie. With a 5psi spring in a Racegate do you obtain 0 to 5psi boost range. And does turning the valve all the way in produce 0 or 5psi? The other variable is the "screw" adjustment, spring tension on the wastegate, does the screw turned all the way in produce 5psi (w/ 5psi spring) and all the way out produce 0psi boost.

No a boost controller's lowest setting is whatever the wastegate spring pressure is. In other words if you have a 5 PSI wastegate spring the boost controller's lowest setting will be 5 PSI. You can only adjust from 5 PSI to whatever the max the boost controller/'turbo is capable of spooling too.