I have a bolt on '00 LS1 with the rev limiter slightly raised, and it seems like ever since I installed the Underdrive Crank Pully(if I remember correctly) my car has started ticking. After reading up some on here I thought it was probably lifter related so I ran some seafoam through the car, and changed the oil after about 200 miles(previously I believe it was 5w30 reg, now is 10w30 synthetic mobil 1) The car seems to tick still and I believe it's coming from the back driver side. I hear it at low RPM and it seems to be RPM dependent. I checked for exhaust leaks and found none, however did tighten some points on the exhaust as well. It sounds a lot like this clip.
http://www.youtube.com/watch?v=4l9hq...ayer_embedded#!

So I'm not sure if it is a lifter tick, how critical is it to replace, and are there anymore steps I should try. My friend said to check the rockers first, and my dad seems to think it might be related to a pulley(the power steering pulley in particular). I will hopefully get a chance to experiment some next Saturday. Any input will be appreciated.

 

Dont really see how a pulley can cause a tick,, Unless you have something in the path of the belt or rubbing on a pulley possibly. Try to get a good listen to the noise. The rockers are rollers, So to check them just back the bolt off and pull the rocker off, hold the sides of the center shaft with your fingers and just give it a spin, if the noise is a bearing on the rocker, you might hear it, or more than anything feel it click. That would be a problem if they are not smooth. If you believe it to be a lifter, be prepared. You have to pull the heads to get them. That means new head gaskets and head bolts.