I'm new to the Mustang world and the StangNet and would like to know what modifications I can make to my mustang that will increase performance and looks without violating the warranty?
First off, if you have a manual, throw out your shifter for a Steeda Tri-Ax or Pro 5.0 huge difference.
Then get some gears, I recommend the 4.10s, they will give much better performance. Then I would go with some exhaust, a catback and x-pipe of your choice. Have fun
Check with your dealer on warranty... they said if I just changed the catalytic converters, the warranty would be voided. (Of course, before then I was going to get a catted pipe, but after that, I went on to an offroad pipe.) Basic mods you should look into: K&N air filer #E-0945, underdrive pulleys and timing adjuster, exhaust, gears, etc. Welcome to the game and have fun!