It is nothing more than putting a spacer between the spring the the retainer screw to add a little more pressure against the bleed-off plunger. There has been much discussion about this. One issue is that more oil fills the top end of the engine and then starves the lower end of the engine for a steady supply of oil. I think they got it figured out with the LS7 by adding the external oil pump that scavenges the oil out of the pan, puts it into a storage container and then draw oil from the storage container to pump through the engine. There are no alignment issues with the LS7 pump, failures are rare and you have a good supply of oil.