Engine knock problem

[gbelous]

I own a 1990 gt, bought it a several months ago and basically since then its had a loud knock from the engine. I'm not exactly sure where it's coming from within the engine, but I'm trying to narrow down the possibilities of where to start looking and how much it might cost to fix with some friends.

(putting oil in softens the knock very slightly, but with a bad oil leak the noise comes back within seconds so I'm not sure if it has any connection to the knock).

It is a constant knock and gets louder and faster as I accelerate. There doesn't seem to be any major loss of power, acceleration and speed feel the same as before. I'm guessing it could be a rod or valve, but what's the best way to find out?
Any other advice might help so toss anything out there.
Thanks!!!!

[CelicaOwner90GT]

yeah i had a 72 nova that did that to me, i spun a bearing because i never gave it an oil change and the oil got to thin and caused to much friction and thats how i spun a bearing, its a bit pricy to fix so i just got rid of the car, because a new engine was gonna cost about 2500, but its up to you