can you give me your suggestion on the best way to set up cold air intake, and how much HP can i get.
Actually, the car is already setup with a cold air intake if you have the stock airbox. If you use a cone filter you can easily fabricate an enclosure around that corner of the engine bay using thin aluminum. You can even insulate the aluminum with duct insulation. This stuff can be found at Home Depot or the like.
In reality, once the car is moving the intake temps aren't much above ambient. When I was playing with Saabs, a board member ran a test where he simultaniously measured the intake temp (in the pipe) and the outside air temp. While sitting, the intake temp rose pretty high (with an open cone filter) but dropped to a few degrees above ambient once underway.