In most cases you probably wouldn't know the difference. You would notice better power with the car cams at higher rpms and on the highway in kickdown acceleration from cruise throttle. If you tow, you'd want the truck cams.

My suggestion was based on my belief that a truck engine would be easier to find and cost less, but if you can find one with all the extras for that price, so much the better. I think the VR4 engine had a nitrided crankshaft... an advantage if you plan to build a lot of boost. Either way you go, you'll probably have to source some parts from the other variant... if you buy the truck engine, you'll have to buy the turbo stuff.... if you buy the VR4 engine, you'll likely have to buy some longitudinal engine parts.

Frank