GM Performance
There have been several people asking what engine or package to buy from GM. (new engine)
Currently, GM Performance doesn't offer a suitable engine/trans package for this conversion. They have three different offerings...
Crate Engine
Connect & Cruise
E-ROD
Crate Engine
GM does offer the LC9 (5.3L aluminum) truck engine as a crate option. Part number 19259918. (~$5,000) This can be used on this conversion. Available from Summit, Jegs...
Connect & Cruise
This package comes with a wiring harness, ECM, and optionally a transmission. Problem is GM Performance doesn't off the 6L80e transmission, yet. Therefore, any package engines won't have the correct ECM and wiring harness.
E-ROD
This package is the Connect & Cruise plus down pipes/cats and is California legal. Here again, since the 6L80e is not offered, it has the same problems as Connect & Cruise. Don't wast you money on this one. You will have to scap the down pipes/cat, exhaust manifolds, ECM and harness. Then you are left with the Crate Motor and no CA compliance.
So what are the options? You can purchase the LC9 Crate Motor from GM Performance, a 6L80e trans from the dealer (~$2800), and a wiring harness from the dealer (~$200), and an ECM from Amazon. This won't work in California as a donor VIN is required for an "engine change". I an not sure what other states require.
Will a Car Engine work?
Car engines can be used outside of California. However, the oil pan and pickup, water pump, and possibly the crank pulley will have to be changed. There are three pulley offsets. Close, medium, and long. The truck water pump is required here and uses the long pulley.
Hope this helps.