I have been trying to diagnose this forever. A few of my friends(one who is a mechanic at a subaru dealership) told me it was the balancer shaft bearings, but I removed the balancer shaft belt today and the noise persisted. I also replaced the rod bearings and the noise persisted.

At this point i'm not sure what it is. It only happens at 2250rpm+ and increases as the RPMs increase. I will post a link to a video of the noise.

http://s30.photobucket.com/albums/c3...t=MVI_2423.mp4

 

Wow, I almost hate to touch this one...2250 and a rattle. Asking about egr cleaning is out....hummm. 2250 is about the time vtek-yes did that for a reason-kicks in....could there be something in the change in the valve train. I'm sure you're already there. Of course I'm going with the 95 as it looks like the 97 is in a transformation, but you didn't state what or which was giving the issue....lol

 

its the 97, those are just old pics. Its together with a F20B. I thought about vtec as well, but its a little early. Tomorrow I'm going to take the valve cover off and feeler gauge the cam/rocker clearance and see if it could be something there.

 

Ok, I was just kind of pokin fun. Please don't take it the wrong way, I like a little fun in my life. So as stated, you were already thinking the same as I suggested...clogged oil passage, weak springs could cause the valve timing/change in lift to be off at higher rpm's, not sure of the state of the engine that was just/recently put in, but then again, who am I...good luck and let us know what you find.

 

Nothing was taken the wrong way, I'm just looking for suggestions, I've tried almost everything I can think of.

I put the engine in 6 or 7 months ago, working on it mainly on weekends. Had tons of problems getting it running, and at one point it was running very rich so I was thinking maybe the gas destroyed some bearings, but the bearings have checked out.