I had a LS2 pump on my last LS1 motor, and moved it over to the LS3 when that was installed. I seem to recall that there was a variant LS3 pump which was more efficient. Is there a more efficient OEM water pump than my existing LS2 which is compatible with my F-body accessory dress?

 

I had an Ls3 but went to an LS2 because the self adj. tensioner on my blower. needed more clearance so the belts wouldnt hit each other. And i personally didnt notice any difference in the swap