It is hard to find a professional system that will give you extreme gains (over 150HP.) because of the user tuning that would be involved. Im not saying that you are not capible of doing it, it's just that the major copanies that produce these kits don't. They do not want to be responsible for engine failure because of a lean fuel curve at 25 PSI or other major problem that can cause explosions. You will always be happier with a custom job.