This is a very good idea! I was messing around the other day and just connected the wastegate straight to the vacuum sounce. It was all around more responsive but of course, it eventually set a code and it's also boosting a little higher than normal but not too bad.

One improvment I would suggest is to put a pinhole oriface in the upstream connector to slow the venting of vacuum when the solenoid dumps. As an alternative you can put a much larger reservoir to ensure enough volume. Connecting a vacuum gauge to the wastegate will be more telling if you have the proper size.

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-Evan


Benz Fleet:
1968 UNIMOG 404.114
1998 E300
2008 E63


Non-Benz Fleet:
1992 Aerostar
1993 MR2
2000 F250