91/92db sounds correct. Last time i was given the test at Warwick pits i was tested from about 1-2m away at 1,500rpm, 2,500rpm and 3,000rpm (supposed to be 3,500rpm but no one was watching so i didnt go that high!)

Over 2.5K rpm my car was illegal (102db) and i was told that "given you have no cat, i'd suggest you keep it under 2.5k so we dont see you again" I have a DB meter on my phone (how accurate it is, i dont know) but the new exhaust is much louder...