High-Performance Engine Controllers

Words: Larry Shepard

There are many names that are used for engine controllers like ECM, ECU or EMS, but perhaps the most common one and the most general is computer. Engine controllers date back to the 1970s but really became engine controllers in 1984 with the introduction of turbos to production engines. By 1993, these engine computers were used across the board on all Chrysler production engines, cars and trucks. Since then we have learned that engine controllers are very engine-specific and definitely do NOT fit in the one-size-fits-all category. Engine controllers tend to be programmed to the vehicle (car or truck), model year of the vehicle (2006 vs. 2004), engine size in the vehicle (5.2L vs. 392) and almost all engine hardware like cams and heads. While there are programmable units that can be adjusted on a PC, ideally the baseline software program is close for your engine and hardware; however, you should be prepared for tech-support consultations. This is a very complicated subject.

An engine controller or computer manages the complete fuel curve through the fuel injectors, one or more per cylinder. Additionally, this same controller manages the complete spark advance curve—total spark advance, the curve itself and the vacuum aspects. It takes a lot of sensors to perform correctly. In researching Mopar® engine controllers for this article, we found that the details on one controller part number could easily fill this whole column, so we’ll just hit some highlights and let you fill in the details by referencing the 2009 Mopar Performance Parts catalog, now available for download at www.mopar.com. If you have any resulting questions, please call the Mopar Performance Techline at 1-888-528-HEMI (4364).

There is no obvious order in discussing controllers so we’ll start with the largest and heaviest. The 392 Gen III HEMI® Crate engine P5153605 is a complete engine assembly which includes an engine-specific controller. The fuel-injected version listed makes 525 hp and 510 lb-ft of torque, which is very impressive. The carbureted version of this 392 crate engine is P5153604, makes 540 hp and it comes with an 870-cfm carburetor. Obviously, on this version the engine controller doesn’t control the carb but the crate engine assembly does include its own, unique controller which manages the distributorless ignition system. The service unit (engine controller only) for the carbureted crate engine is P5153608 while the service unit for the fuel-injected unit is P5153528. Both of these controllers are programmable so they have more flexibility and can be used on many different engine projects.

In the last few years the Gen III HEMI has been very popular for engine swapping and many unique applications. The current Gen III engine sizes are 5.7L, 6.1L and 392. While the 392 is the largest and most powerful, the 5.7L and 6.1L have been used in production vehicles and are available at many salvage yards. When using this approach with a used engine, a word of caution: consider the engine’s front cover because truck engines and car engines use two different front covers. In general, the truck front cover locates the accessories higher. This could be advantageous for street rods with tall, narrow engine compartments but not desirable on other wide, low-hood engine compartments.

For several years, Mopar Performance has sold a 5.7L HEMI Crate engine (Gen III). The service engine controller for this carbureted 5.7L HEMI crate engine is P4510816, or P4510342 if it was a fuel-injected version. Both of these service units are non-programmable. This means that these units work best if the engine stays close to the stock 5.7L condition. Recommendations: use with the stock 5.7L cam only. For swapping any of the Gen III engines into non-production-based vehicles you will need an engine wiring harness like P5153606AB (for programmable engine controller, with 5.7L HEMI with carbureted intake and 2003–05 coils). There are many engine wiring harnesses, so look up the one that best suits your installation. Note that in the engine wiring harness description the specific coils are mentioned: 2003–05 coils and 2006-and-later coils. Both of these coils are standard production units and are serviced at your local dealer. The year of the engine defines the coils because the valve covers changed in 2006 and the coil mounts on the spark plug and valve covers.

Another item that is used in the fuel injection system is the throttle body or carburetor and its basic specifications are very important to the controller. The 525 hp 392 HEMI crate engine uses an 80-mm single-bore throttle body which is also serviced (P5153689). There is also a 4-barrel throttle body P4510363 which requires a new intake manifold. The 5.7L HEMI crate engine that used the carburetor was based on the 600 cfm Holley vacuum-secondary unit. If you want to use an Edelbrock/Carter carburetor, then select a 600 cfm AVS unit but expect to do some calibration work.

To race† a 5.7L/6.1L/392 Gen III HEMI in many classes, including Stock classes from A through F and all Super Stock classes, you must have an SFI damper. The damper for use with the truck timing cover is P5153631, and the one for use with the car/Jeep® timing cover is P5153630. These dampers are unique because the multi-groove front belt is driven by the standard damper, so these SFI dampers have the grooves cut on the outside diameter. Both dampers come with a keyway machined in. Tip: The production Gen III HEMI engines do not currently come with keyway-grooved cranks. Mopar services the 392 crank—P5153578 (3.795" stroke)—with the keyway groove machined in. This could be important if you add a supercharger to the engine. If required, have your local machine shop add the keyway groove to your crank and use one of these SFI dampers.

Before we leave the 5.7L HEMI fuel injection topic, there are two powertrain controller upgrades for the 5.7L HEMI engine when used in cars: 2005 Charger/300/Magnum P5153331 and 2006 Charger/300/Magnum P5153450. These are best used with HP camshaft P5153325AB and lifters P5153570AB. Also consider adding the transmission(automatic) controller upgrade P5153332, for 2004–06 Charger/300/Magnum 5.7L engine. I recommend using with the controllers listed above.

The fuel injection kit for use with the 360 Magnum® Crate engine is P5153590 (automatic transmission). This kit includes a JTEC engine controller. The kit is based on the 4-barrel throttle body and single-plane HP intake manifold and 33 lb/hr fuel injectors. The A-engine ended production in 1992 and the Magnum family went out of production in the early 2000s. Getting new or HP parts for these engines has been difficult, especially cast iron blocks. The new Magnum cast iron blocks— P5153579, 5.2L with 3.910" finished bore and P5153452, 5.9L with 4.000" finished bore—have a trick feature. They have a small hole drilled between the tappet bores of the same cylinder. This hole is used to hold the special dog bone tappet locators (P5155275). These dog bones come with special flanged screws and small springs that allow these dog-bones to be used with the production Magnum hydraulic roller tappet without the production spider. This system could be added to older HP blocks designed for A-engines and this opens up the door for hydraulic roller cam use in these older engines.

If you want to add engine controllers and fuel injection to your A-engine or Magnum small block then you need an intake manifold to hold the injectors. The Magnum engine has a single-plane aluminum intake for use with the standard 2-barrel throttle body like P5007398AB (with EGR). The 4-barrel throttle body version is P5007790. Both have the injector bosses already machined. The 426 HEMI (Gen II) should use P4876188 which has bosses but will require machining. The best choice for the 440 RB-engine is P4529463 but it will require the bosses to be added and machined. Tip: The key to installing electronic fuel injection onto 426 HEMI (Gen II) and 440 RB wedge engines is a dual-pickup (dual trigger) distributor which is available from Accel (Mr. Gasket).

The Viper V-10 package also uses an engine controller in production. The high-performance version is P4510172AB (2003–06) and P5155254 (2008–09). There are also HP engine controllers for the Ram SRT10® truck built using the all-aluminum Viper V-10 engine like P5153335 (2005 version – the ’04 and ’06 versions are also available).

There are turbo upgrade kits that include four injectors and an HP engine controller for the turbo Caliber SRT4® like P5155175 and also for the turbo Neon SRT4 like P4510910 (2005 version) and for the 2003–07 turbo PT Crusier models like P5153846 (2007 without ABS). See the Mopar Performance parts catalog or view the catalog at www.mopar.com for more part numbers and added details. Additionally, there are engine controllers for many of the older Neons like the ’95 DOHC (P5007034).

The first electronic fuel injection kit that Mopar Performance put together was designed for the 4.2L in-line 6-cylinder Jeep engines mated with automatic transmissions (1981–90), kit P5249686AE. The manual transmission version is P5249610AE. It still offers greatly increased power and torque and many off-road features desired by off-road customers. This kit includes a special engine controller which is also serviced separately: P5007146 auto, P5007147 manual. Don’t forget that these kits require a special crank damper—like P5249687 (V-belt version).

Whether you are swapping engine controllers and fuel injection parts onto your carbureted engine or swapping a fuel injected engine into a previously carbureted vehicle or even a newly built vehicle, you will have to sort the complete package out once it is running. This sorting-out process is called fuel calibration. To help with any calibration process, it can be handy to have a boost/vacuum gauge, like 77060032, installed where you can easily read it. This gauge design has the Mopar “M” in the center of the face and reads both boost pressure and vacuum. You will also need a tachometer like 77060057 which also features the Mopar “M” in the center.