i used the ERL mf2 fully mappable fith injector kit, which i had doubts about first but believe me it was amazing in the end. It does exactly what you want it to do and if you are one of those who wants to keep the mfi setup then you cant go wrong with one of these. My metering unit had no mods and with fith injector i ran 250 no problems at all. I highly reccomend this kit to anyone and believe it or not it is so easy to fit. My electrician charged me 20 quid to fit as i told him exactly where to splice and solder.