well i belive that it is 18mm for it. If you can just look around for aftermarket swaybar replacements in this forum they will tell you what the stock diametere is in the conversation
------------------
aLwAyS lOoKiNg To Go FaStEr
2000 Crystal Blue Base Prelude
OEM Body kit
AEM CAI
EIBACH PROKIT
Dc Front Upper Strut Tower Bar
Dc Rear Lower Strut Tower Bar
Mobil One Synthetic 5w-30
AUDIO:Alpine 7965 CD deck,Mtx Thunder 304 @ 375 Watts, Mtx Thunder 302 @ 400 Watts Powering A 12 Inch Mtx 8000, and Alpine 12 Disc Cd Changer
------------------

aLwAyS lOoKiNg To Go FaStEr
2000 Crystal Blue Base Prelude
OEM Body kit
AEM CAI
EIBACH PROKIT
Dc Front Upper Strut Tower Bar
Dc Rear Lower Strut Tower Bar
Mobil One Synthetic 5w-30
AUDIO:Alpine 7965 CD deck,Mtx Thunder 304 @ 375 Watts, Mtx Thunder 302 @ 400 Watts Powering A 12 Inch Mtx 8000, and Alpine 12 Disc Cd Changer