I have never replaced a LS1 oil pump before so I have a few questions. Is there a gasket on the output side of the oil pump? How does it connect to the block. How does the pump make contact with the block when I shim up the oil pump to make room for the double roller?
Dale

 

The shim includes the hole where the oil passes through to the block. And no, there is no gasket there ever. It will be very obvious what I mean once you get to the point of shimming the pump.

 

Thanks.
Dale