So my old 383 decided to start dumping oil everywhere, so i tore into it and found the front edge of the pan gasket where it meets the timing chain cover is where its coming from. But heres the kicker, the inner edge of the lower part of the chain cover where it "holds" the gasket has seperated from the cover making a 1/16" gap where the oil was basicly pouring out. My question is why did this happen? And how do i prevent it? I will attach a picture in hopes of trying to explain myself better.

(dont mind the scribbles, that is just covering up the previous crap i wrote, lol)

 

Heres a little more info on the engine this happened to, its a 3970010 block .030 over, 400 crank, head work including 2.02 valves, comp extreme energy cam, and a high volume oil pump. I cant remember the exact cam rates or cylinder head cc's off the top of my head, as i built this engine in 2007 when i was 16 lol