op go to padres build journal. He has the numbers to back up the fact that shorty headers with hi flows make decent gains. His numbers are based on track times before and after each mod. Shorties with hi flows keep your warranty and don't throw codes. They don't make the power of long tubes but they aren't as bad as people post.
http://youtu.be/Bwdo5895T9s this is a video of my car with...solo hi flow ..jba shorty headers....magnaflow muffler delete exhaust.