Info provided by Calvin of Nivlac57 youtube channel

Stock

All of the intake manifolds are the same from the factory. They are actually really nice intakes. I understand the people who think they are ugly. We have had them up to 16 psi of boost. I'm sure they will handle much more.

Sheet Metal Intake

For those what don't like the stock manifold or can't fit it under the hood, a sheet metal intake is not hard to make. The nice thing about a Vortec 4200 is the injector bungs are cast into the cylinder head, so you don't have to deal with getting them lined up perfectly.

Adapt to 2JZ Plenum

I have been attempting to design a set of runners that will adapt to a 2JZ bolt on plenum. It would probably kill power in naturally aspirated form, but with a turbo, I bet it would work great.