to my knowledge the engine had a fresh stock rebuild when i got it(from the person who originally bought the engine). and judging by how new all the engine parts looked i believe it was actually rebuilt. engine was on stock turbo with a isis plenum installed by previous owner. im on my second cylinder head thanks to bad valves in the first one. (that head is for sale if anybody wants it lol)
but anyways...i tore the valve covers off the engine and let it run for a few seconds and determined it was probably the lifters making the noise. so i put some new oil in it and it helped a little bit.
after a long day at work i decided i wasnt going to let my car go out like a bitch so i commenced to beating the shit out of it on the way home. and much to my suprise the noise completely went away.
so im 99.9% sure my lifters just bled out due to the crap oil that had 5k miles on it.
and its been running good ever since.