Camaro z28 1984
Can it make a difference if I move the pcv valve to the left if it is to the right of the engine and move the breather to the other side ?

 

Should work about the same.

Why would you want to do this?

 

I bought my new chrome valve cover and the holes are different places !

 

Should be in the same places.

Valve covers for these engines have a definite intake and exhaust side. They only go one way. If you put them on backwards there's a good chance the rocker arms will hit them; and if you look at the gasket flanges, they're often different there too: the intake side doesn't have as much of a lip, to avoid interfering with the intake manifold itself.

Put them on so that the PCV system holes are at the front left and right rear of the motor, as seen from the driver's seat. Hook everything back up like it came. Things will work out MUCH better that way.