Ok, I have a friend with a 95 LT1 that runs perfect,uses no oil and has plenty of power. The car hass good oil pressure but I have a question about startup. When he first starts the car its makes a noise from the lower half of the engine for a few seconds and stops completely after running for a few minutes. Kind of like a brief lack in oil pressure.
Just wondering what you guys think is causing this? He is afraid to cam the car due to the noise But I dont think its a real issue. It is not a lifter as it is coming from the bottom of then engine.

Any thoughts other then a lifter?

 

The LT1 will often produce a bit of piston slap on cold start. Is that what it sounds like?

 

No..sounds more like a short knock. Like it sounds right after an oil change when the oil hasnt fully circulated.