Massive Response:
-D16 turbo setup would be pretty awful compared to a OEM B-series high compression build or K-series. No matter what you would do, the power band would be a bit too violent and would place power in the wrong places. I know they are inexpensive and work, but I just can't see myself getting persuaded to go that route. That faggot Bisi would have to volunteer to build me some magical D-series for pennies for me to think about going that route.
-Yes, you can make it street legal in most states. You have to call the DMV and ask for a packet of information on how to title a kit or custom car. Then follow the protocol. Most states want the standard stuff: lights, windshield, wipers, indicators, ect. You need engine documentation. Depending on state, you may or not need SMOG crap.
-I will never put a centrifugal SC on anything, ever. Twin Screw>Roots>Centrifugal. I do have some fears with the K-series faggot transmissions. They aren't cheap enough to break often.
-If I'm buying overpriced engines, I'm buying Honda garbage. If someone gave me a free VW engine if I promised to use it in this vehicle, I'd have to mull it over.
-Shadow, you're retarded.
-B16 is faggot shit no matter how you figure it. If I went B-series, I would only go 1.8L or bigger.
-fysh, as much as I like that idea, I also like the idea of having an open engine bay. Throwing a V8 in with the matching transmission would probably fit, but then I'm cramped. I hate working on tight engine bays. 4 cylinder option is really just for the ease of fitment/working.
-Has to be 4 cylinders for all of you others suggesting larger or less than.