I’m having trouble controlling boost with my new Greddy Profec B on my XS T04S single turbo kit. The way I have the Greddy Profec B hooked up is as follows:

Step motor:

HKS Racing Wastegate line to the OUT on the step motor

Charge pipe (right after the turbo) to the IN on the step motor


Controller:

Small diameter line coming from controller goes to a T on the upper intake manifold which splits the boost guage and boost controller.

Switches on the back – set for external wastegate. I tried both ways (with and without over boost)


I’m pretty sure this is hooked up right. Is it? I can not keep boost down. I keep boosting to 14+ all the time.

Let me know what you think. I really want to resolve this before I pop!

PS:Is there an adjustment on the HKS Racing Wastegate?