stand alone ecu's are completely tuneable computers. they can hook up to most any kind of engine and depending on the ecu have a wide range of tunability as far as fuel maps go. tuning is done with a lap top computer. some stand alones are HKS F-con-V pro, APEXi power FC, Autronic(australian and also what we use at our shop), Motec... . but there are also plug and play ecu's that AEM offer which require absolutely no wiring of any kind, just take your stock ecu off and plug in the AEM. expect to pay about 2 grand for a good one (like Autronic) and even more for Motec. the japanese brands need certified dealers to install and tune so there might be limited shops that do those.