What years are your LS engines based from?

LS3 2008-2017

They are all mostly based off the RPO engine code LS3.  Which was produced by GM from 2008 thru 2017 and are an aluminum block Gen IV 58x crank 4x cam model.   Our 408 LS does use the 6.0 cast iron blocks that are cast 12576181 and can be built with either the 58x/4x combo or as a short block using the older Gen III 24x/1x setup.