With the upcoming SCCA Majors at Laguna Seca it looks like the sound windows are now gone with all sessions at 103dB. Question for everyone and those with insight to the rule makers: Are we required to run the Laguna Muffler or can we just run the stock muffler?

March GCR states:
J. EXHAUST
Exhaust may be plated or coated. Repairs may not alter the configuration or tuned length of the header or tail pipe.
Standard Muffler Kit G1190523 (including Standard Muffler P/N 390523) is required for all events. For tracks with stricter sound requirements Quiet Muffler Kit P.N G1190524 is available as a replacement for that event. Muffler packing of any kind is not permitted. Tail pipe may be tack welded to the muffler.

I read this to say we can run the standard muffler for the April Majors Event.

When I asked tech at driver school about the change in sound restrictions for 2020, I was told that the Laguna Muffler would no longer be required at ANY San Fransico Regional races including Laguna Seca and Sonoma.

Though the discussion was about regional races, I believe the same applies to Majors.