your best bet for the money is cosworth managment on the standard mfi manifold as this flows just as well as an efi manifold except there is less parts to change! but you will need an adapter plate between manifold and head for the injectors and/or head mods to the ports for the injectors to spray through but saying that mfi is good for arond 250-300bhp with a 5th injector ive had no problems myself with mfi and my car was used for daily duties till the gearbox broke AGAIN!!!!!!