Hmmm.... why the magic number of 15psi? Better to set a power goal rather than a PSI goal. As a bunch of us found out yesterday, you can make 120hp or 230hp on the same boost... it's all in the tune. Keeping in mind that the car weighs about 2200lbs... HOW MUCH POWER DO YOU WANT TO MAKE? Then go about building a kit that will get you there. Setting a PSI goal doesn't do anything for you.
First, read this:
Then go here and check out every page on the website:
Order Maximum Boost, or they usually have it at B&N or Borders:
Then go here and check out all their products:
To get a good idea of all other major performance products for Miatas, this website is a good place to check things out, price products, and compare:
A turbo should be low on your parts list for a stock car... there are quite a few things to upgrade IMO before adding power:
Tires at least... the stock 14's are really light though
Brakes... just pads and braided lines to start
That'll be a good start. Your best bet if you plan on modding right away is to buy a car that's already modded, not necessarily turbo, but at least with the basic suspension bits and maybe some performance stuff. Check out the classifieds lower on the main forum page and visit www.miata.net
in their classifieds. Lots of modded cars for sale.
You can't do better for a piggyback for the money than Emanage Blue. Lots of support around here for it. A used kit with the cables and injectors is the cheapest way to get full control of your fuel and spark. The new daddy on the block though is the plug-and-play Megasquirt.
Also, good advice around here, learn to use the . button... you know, make sentences and stuff.