So I finally got the old gal running (ish anyways). It makes an incredibly loud noise, almost louder than I'd think a rod knock could be. The strange thing is it still develops over 50 pounds of oil pressure. The valves all seemed to adjust good, and compression was consistent across all four cylinders. When I did the compression test it was on a crappy, and half dead battery, and a cold engine. I never got more than a few revolutions out of it per cylinder. All four were right about at 200 psi. I know there's an exhaust leak where the header attaches to the exhaust manifold, but I can't imagine its enough to make that noise. The only thing I can think of is wrist pin. Any other theories? I'm at a loss

__________________
1969 220d - soon to be a reliable daily, and so the tinder profile can say I drive a Mercedes