even if you have an stand along computer, you would still need to your car to be dyno tuned~ Dyno tuning by flashing your computer would definitly give you some gain on the horse power, but it's better if you get the injectors and boost controller. This way you would be able to get the best out of it. You would need to change your interecooler too. Stock intercooler won't be able to take 14psi (1bar)..... I hope this helps~