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spuggy spuggy is offline
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Join Date: Jul 2003
Location: Glorious Pac NW
Posts: 3,329
Originally Posted by Pork Chops View Post
Diagram is correct, IMO.

If you're using the common 35-series (3 port) MAC valve, port 1 is normally-closed, port 2 is normally open (vented to atmo via port 3).

If you've got some other variant, you're on your own - but the diagram is consistent with a MAC solenoid.

Connect the intercooler/throttle body etc to the side port of the Tial and port 2 to the top.

Until the controller switches on, all the boost goes to the side/bottom of the wastegate, and you're running on just the spring.

As the solenoid activates/duty cycle goes up, it adds boost on top of the diaphragm, increasing resistance above the spring rate.

NASIOC guys say to leave the brass "muffler" out of port 3, BTW.
'77 S with '78 930 power and a few other things.
Old 07-18-2019, 06:22 PM
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