If positive displacement is what you are looking for I would do a screw style supercharger. They are more efficient and have lower intake air temps than the TVS style superchargers.
I would look at Whipple, Lysholm, or Kenne Bell.
These will all give you great low in power and since they are a srcew style they will give better high end power than a TVS style rotor.
Another route to go is a centrifugal supercharger. This is what I have had on every vehicle I have owned since high school. They will be the most efficient and offer the best mid range and high end gains. Also since the supercharger does not come on as strong down low you will see better mileage in town over the positive displacement.
If you look at this style I would look at Vortech Engineering.
That being said. This 2010 Tahoe I just got I tried a Lysholm Supercharger from Vortech. I love the low end power, but wish it had a little more on top. It will always be a trade off. I also get about three to four miles per gallon less in town with the way I drive, but get about 17 mpgs on the highway.
I think a 2.3L supercharger will tap out at about 550 RWHP with supporting mods.
