Manual AND electric boost controllers?

[blackyman7]

I recently bought a 97 gst and as I’m looking over everything and replacing worn out hoses and what not I come across a Hallman manual boost controller and it is hooked up to wastegate and a nipple on the j pipe. Inside the cab I found a Greddy Profec B II boost controller and it is hooked up as well. I followed the line from the Greddy and it’s t’d into a vacuum line to the manifold. Now my question since I’ve never owned a turbocharged vehicle before is can you run both and not have any problems or will it run better with one or the other?

 

[dustyboner]

the greddy should have a boost control solenoid installed were the manual boost controller is installed. The line going to the manifold is so the controller can read the boost level.
So obviously it won't control boost without the solenoid.

maybe the solenoid died and was replaced with the manual boost controller.

 

[Vegas Smith]

It’s not entirely clear from the post but you can have manual/electronic combos that people used back in the day. You controled the mbc with an electronic to give better control. By your wording in the post it looks like you’re running the manual to control boost but the electronic is still hooked up? Maybe previous user was using the greddy as a boost gauge, boost cut failsafe or just plain left it connected out of laziness?