Is it possible that someone sold you the wrong spring? Were they different in size or color? I know the springs for my Tial wastegate have a little paint on them to identify the rating. The 1 Bar spring and 0.6 Bar spring are both blue. The 1 Bar one is larger though. You are correct that the upper port is only for the electronic boost controller. You can expect the wastegate to open partially before you hit its rated boost pressure. Every psi of boost tries to compress the spring further and open the valve further. It should hit a happy place and maintain boost pressure around its rating. Don't expect it to be dead-on though. You need a boost controller to really dial it in and minimize early opening.

Corbin
'95 ESI-T

Now with more power and fewer leaks



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