Shoot, I'm trying to remember. This actuator works in reverse of the vac actuator. Normally open is now closed. Which means boost is always available until it builds up and acts upon the actuator. With the rod length longer it wont actuate until the 14PSI/.95 BAR of pressure builds up ( I believe that is the setting of the special actuator). The adjustment allows you to set a lower amount. Up to 91 specs call .85-.95 BAR (12.3-13.7 PSI) and 92-on .75-.85 BAR (10-12.3 PSI). Not sure what a couple additional PSI will do. But I understand that More Air with out an increase in fuel = higher exhaust temps not more power.

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92 300D 2.5L OM602 OBK #59

When my actuator was first installed the shaft was about 7mm too long. This caused the wastegate to always be open which resulted in no boost.

I think the question is, "can the correct length (I believe it is 107 mm but you should check) be set without shortening and cutting threads. Just take the part out of the box and see if it can be set to 107 mm.

If yes and you do not want to cut the threads go ahead and try. If not cut the threads. It's so easy you can just err on the side of caution and go ahead and shorten it or you can not shorten and then tell us if it works.