knocking/grinding sound from engine bay

[Maikoool]

got a sr20det, recently the crank wasn't torqued so the bolt came loose and pulley came off, then i fixd it up and torque it to 112lbs. the hole where the key goes did change, it was like |_| and now its like \_|... my friend who has built sr20s for a long time said just replace the key, should be fine.. so i did.

after ~2weeks running, everything was fine... then in the morning i started it and theres a knocking sound...as if you got something rattling or something. i rev'd it and the note of the sound did not change, it sounded the same.

anyone have a idea what this could be?

[themadscientist]

Yikes. Does the engine feel down on power or is it just a noise?