It seems like a good buy, the 02 cobra engine is worth more then 1k by itself. You dont have to change the transmission but if you are going to go the supercharger route then you do need to change the transmission. The hp output with a supercharger will be too much for the transmission, it will kill your transmission quickly. As far as superchargers go, it is a great mod for the 02 cobra engines. They do great with supercharger. As far as the type of supercharger, I would go with either a twin screw supercharger like a kenne bell or whipple or a roots supercharger like the eaton that comes stock on the 03/04 cobras. Owners of the 03/04 cobras often swap out there eaton for a kenne bell so you can pick up an eaton supercharger with low miles for an awsome price, probally 70% cheaper then you would spend on a new twin screw supercharger. With the eaton you would have one fast car. That is the route I would go with. I own a 04 cobra and have a decent amount of knowelege in cobras and stangs. I am going to swap my eaton out for a kenne bell sometime within the next 6 months. My eaton is also ported by stiegmyer so it has about 100 more hp then the stock eaton superchargers. If you are serious about getting a supercharger or if you have anymore questions feel free to give me an email. Good luck and have fun.