head noise, cam bearing?

Hello, I have a 2000 Prelude SH. There is a slight tapping noise when idling and accelerating from the head. when the throttle is let off the tap turns into a knock as rpm's drop from 2300 to idle. I have used a mechanics stethiscope to listen to different parts of the engine. It really sounds like it is from the exhaust cam by the pulley. Knocks real loud there. Do these vehicles have camshaft bearings? If so, anyone have to replace theirs? If not anyone have an idea of what this is. Vehicle runs strong with only minor mods, CAI, full exhaust, suspension. Thanks in advance for all your help. Also what camshaft upgrade do you recommend? Which company and maybe a shop in lower NY to have them installed. I am one hour north of NYC.

Run a compression check on the motor to make sure the cylinders are holding pressure. You may just need a valve adjustment. No one is gonna be able to tell you what is wrong without you doing some testing to be able to cancel things out.