Interesting comments from Excellence.
The resulting noise is better than any 911 Carrera in recent memory, eclipsed among modern Porsche's by only the 996 GT3 and Carrera GT - both of which play their music to thrilling, intoxicating red-lines well past 8000 rpm. This car's short-stroke 3.4 can't match the exhilarating nature of those exotic power plants at or near their red-lines, but that's only because it's not been allowed to. The tach needle in the Cayman S sprints past 6000 rpm as if it wants to - no, needs to - get to eight grand and beyond. It's too bad the rev-limiter cuts in at 7300 rpm.
In this drive, on these roads, it will do so often. That because the Cayman S' 3.4 liter flat six is so creamy at 6000 rpm that it can deceive a driver into thinking he or she is at, say, 4000 rpm. Back on curvy country lanes, both of us exit a few corners and trip the limiter. Every time, the boxer six felt and sounded like it was at 4000 rpm or so. But the needle was sitting at six grand, just 1300 rpm short of the rev-limiter. It's a mistake we haven't made in a 3.6 and 3.8 liter 997s -or -oddly, in a 3.2 liter Boxster S.
The reason is this 3.4-liter version of the 987/997 motor feels far more eager than any of the three power plants listed above. The sprint from 6000 to 7300 rpm is positively electric, as if this engine is closer to the normally-aspirated GT family than its Boxster/Carrera roots should allow it to be. Like the underrated 3.4 liter engine Porsche used in its 1999-2001 996, the Cayman S' flat six is far more elastic than its cousins - as if this is the exact displacement, bore, and stroke it was really meant to have.