ok, found it:
Softronic Race Plenum -
additionally, the 986 flap is open between 3120 and 5120. so it would be closed over 5000 when it should be open. odd that the 986 flap closes at 5000 while the 987 flap stays open to redline. ps, the 997.2 plenum has a flapper in it too, so they have used it on the 911.
apologies for any hijack.
Threaded Mode
