What Is Going On With My Rb20 ? Strange Noises

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Hi!

Recently I started to notice my RB is constantly having that strange noise.

When I swapped one in around march this year, it was ll mint. No strange noises what so ever. Then about a month ago, I decided to up the idle to 1k to run with AC, I did it to prevent engine stalling. Was to easy to stall when braking, no fun. When upped to 1k, no stall problems. Revs did drop, but didn't let the engine stall.

I think that time it started to develop that strange noise from the top of the engine.

Its not viscous fan, cause if u hold it and turn on the engine, the noise is still there.

Engine doesn't eat oil, doesn't smoke, drives ok.

I've installed splitfires recently and still I can see some blue electric discharges in the dark. Don't think it could affect something though.

I did an oil change yesterday with silver Mobil 1 5w-50 fully synth., its quieter now, but its still there.

VIDS:

When 1st installed:

With intercooler on LOL

http://www.youtube.com/watch?v=WI-k8aTVI2o

Can't hear any abnormal noises )

Now see those shot today. Went to check the engine Turned the idle down to around 800 before shooting:

http://www.youtube.com/watch?v=2jlZH4TxqUw

http://www.youtube.com/watch?v=ceLwB-sYOhQ

http://www.youtube.com/watch?v=DrzL-XFOK8E

(Last vid(number 3) at around 0.36 u could hear a bang or bump while revs drop, wtf is that ? Detonation ? Or is it just fuel exploding in exhaust.

1st time I hear that and so loud. Only did it once).

Now this one shot around 2 weeks ago with ~1k idle, and with one of the viscous fan blade hitting the radiator. So that flapping/tapping sound.

But the buzz is still there.

P.S.

If I turn the idle down to 600 or so, there is little to no noise at all.

Some one tell me whats going on !

Thanks!