Tools Needed: Ratchet, metric sockets and combination wrenches, Phillips and a flat-blade screwdriver, wire cutters, wire crimpers, utility knife, heat shrink tubing, wire ties, soldering iron, electrical solder
Difficulty Level: 4.5 out of 5
|Parts List||Street Price|
|AEM EMS-4 Universal Engine Management System||$759|
|AEM EMS-4 Full Universal Harness Kit||$240|
When it comes to plug-and-play engine management systems, AEM has led the way with its EMS and EMS Series 2 systems. As the popularity of the EMS has grown, so has the demand for a universal standalone EMS. To fill this demand, AEM recently released the EMS-4, a highly-capable standalone system that is not only compact, shock and weatherproof, but also budget-friendly. Although designed with Powersports in mind, this mini-version of the Series 2 EMS can run almost any 4-cylinder engine and best of all; the tuning can be done through the user-friendly AEMTUNER software. With a street price of roughly $800, this system is a great alternative for race cars, off-road vehicles and custom engine swaps, especially with older vehicles which don’t require the extra bells and whistles that the EMS Series 2 has to offer.
Keep in mind that the EMS-4 is not for everyone. Being a universal system, it must be custom wired either using the EMS-4 full universal harness or the basic plug and pin kit. While the labeling and grouping on the full harness makes it much easier to wire the system, don’t expect to get a full step-by-step instruction sheet for your individual application. This is designed to be installed by an experienced installer and the instructions assume that you know your way around a fuel injection system. For most people, it’s much simpler to start out with a plug-and–play EMS or Series 2 EMS system. But if you happen to be working on a less than popular engine or car that does not have a plug-and-play option available; the EMS-4 is a great bang-for-your-buck alternative.
Being in need of an engine management system capable of running the ITB setup on our SR20 swapped Datsun 620, the EMS-4 seemed to be a great option. While we could have started out with a full factory SR20DET harness and a Series 2 EMS, we thought it would be cool to tailor fit a new harness for the engine and at the same time get rid of all the unnecessary wires and connectors. More importantly, we wanted to save a few bucks and to gain some hands-on experience with the EMS-4. As always, we’ve documented the entire installation and are here to bring you the step-by-step process. Our goal is to give you a better idea of what’s involved in the installation and at the same time, educate you on the basics of a fuel injection system.