LT5 technical problem

[8upZR1]

Hello all, you may remember my previous posts, I had a no start problem a few months ago. Much has happened since, but still no action. well sort of. I have not touched the car for about 2 months now. Last night I pulled the passenger valve cover to see if I could find any problems. None to be seen. I then put the plug wires on the plugs and cranked the motor without the valvecover on. It fired, and ran, and spewed a geiser of oil. But it did run. I put the valve cover back on and.....no luck. Still the same problem. Anybody have a clue? Should I just run the motor sans valve covers? Maybe Ill make the switch to mineral based oil first.

My wife suggests swapping valve covers (typical woman) but I think Id rather not. My theory is as follows.....Oil pressure is pumping the lifters up and causing valvetrain to stick open. Is this possible? Are there any oil restrictors in the heads? If anybody knows, Ill be nice to you.......