I tried this and I can tell you what happens. I started with a small chamber and increased size up to about 100cc. It does, in fact, smooth the shift dip but the down side is that a chamber large enough to smooth the boost response will also trigger a code because the ECU tries to reduce boost at cruise. Since the volume of the chamber slows down boost changes, the ECU thinks the wastegate isn't responding to the command to reduce boost.

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-Evan


Benz Fleet:
1968 UNIMOG 404.114
1998 E300
2008 E63


Non-Benz Fleet:
1992 Aerostar
1993 MR2
2000 F250