What year?

The line on the wastegate iin a '90/'91 SDL is pressure, not vacuum.

If you're getting to 1bar, the overboost protection should be shutting down fuel enrichment as if there's no boost (via ALDA pressure line / switchover valve).

I'm not sure that the original turbo is capable of holding up to 1.7bar, my local turbo shop tells me that it's easily good for 1.2bar though.

Just FYI, according to Mercedes the factory settings on the .970 are .85bar, and that's good for 135,000rpm.

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Gone to the dark side

- Jeff