My 00 si has an exhaust cam that doesn't resemble the 89-91 or the 92+ cams but 1 thing from both of them. I found a thread with someone with the same problem but it never got answered. Here goes the pic he posted. Notice it has the non grooved end of the 89-91 cam but the raised cam bearing of the 92+ cam???????????

http://bit.ly/pbAAH8
http://bit.ly/nMeuuE

 

Get a micrometer and measure it. Problem solved.