Get Corky Bells turbo book. All the formulas for selecting the correct turbo based on flow are there. Once you do the math then find a turbo with the correct flow chart and ar ratio. I would think that something in the gt30-35 area would be perfect for what you are looking for. Twin scroll and ceramic ball bearings for a fast spool. Also get the shortest and correct size intake tract. If it is full race purpose car a new intake manifold will really help.
Remember that good ducting is as good as sticking the front mount right in front of the radiator. Look at porsche.