The first thing to do, just like any project is to gather information.
I would highly recommend starting with reading these books:
Maximum Boost by Corky Bell http://www.amazon.ca/Maximum-Boost-Desi ... 0837601606
http://img.amazon.ca/images/I/51uy0K...500_AA300_.jpg
Turbochargers by Hugh MacInnes http://www.amazon.ca/Turbochargers-Hugh ... 729&sr=1-1
http://img.amazon.ca/images/I/51cujW...SH20_OU15_.jpg
Turbo: Real World High Performance Turbocharger Systems by George Matly http://www.amazon.ca/Turbo-World-High-P ... pd_sim_b_2
http://img.amazon.ca/images/I/516a2w...500_AA300_.jpg