Corvette Performance - Motor Knocking, Plz HELP! c5 z06

c5 corvette z06
65k

Ok guys, i pulled in my house one night and noticed a burnt oil smell. Popped the hood and saw oil spewing from intake manifold gasket, so the next day i pulled everything off replaced the gaskets and go to start her up and BAM

A knocking noise, so i had a mechanic buddy come over and said i didnt bolt down the manifold correctly so we took it all off again and did it all over, cleaned everything up and bolt it down coreectly and its still knocking.

So today, we decide to take off the valve covers to check the rods, springs, rockers just everything visual. Everything was good rods were straight. Had some extra coil packs lying around and tried those on just for a shot too, and still it is knocking.

It has never knocked before. And doesnt have crazy mods, Just intake and a tune. So i have no idea what is happening or going on. Dont see why something this bad could come from replacing gaskets, and no i didnt drop anything in the motor

IF anyone can help, i would greatly appreciate it!!:chug:

How is the oil pressure? SES light on? Could be a lifter, but that really wouldn't explain oil spewing out. SOunds like a combination of problems headed up at the same time. I don't think it is anything to serious. If it was a rod knocking you would have loss in oil pressure and the noise would be extremely loud along with a loss of power that would be quite noticeable.

Pressure is fine, not sure on the temp.
yeah a buddy said it could be a collapsed lifter?
Engine light is on for a p0300 misfire code.
The oil is black but was changed around 4k at the most ago. RP.

Pressure is fine, not sure on the temp.
yeah a buddy said it could be a collapsed lifter?
Engine light is on for a p0300 misfire code.
The oil is black but was changed around 4k at the most ago. RP.

Did you change the oil before the knock or after? I had a very loud knock when a lifter's roller broke. I discovered needle bearings in the oil before I got the motor torn down.