5.7 Hemi MDS delete tune: MDS and VVT with HP Tuners

No, not yet. This guide and the Mopar Full Custom offer cover the 2005–2014 5.7, 6.1 and 6.4 controller families. A 2015 or newer Ram 1500 is outside that window, and many of those trucks use the 8HP. We do not have a 2015+ controller or 8HP tuning procedure, so we cannot take a Full Custom order for that truck. The RFE guide also excludes the 8HP, the 66RFE and the 68RFE.

If you have a 2015+ truck, email support@tunebible.com with the year, engine and transmission. We will note the request and tell you if coverage changes. We will not promise a date. For a 2005–2014 truck, the shift work is on the 545RFE and 65RFE guide. NAG1 is a separate computer and is confirmed in the order notes.

The model year gets you close. The engine family and the file settle it. Use the file as the authority, not the badge. A 2009 badge does not prove an Eagle phaser, because the 6.1 remained in some cars after the Eagle 5.7 arrived.

A 6.4 badge does not prove MDS, because the configuration still has to be checked.

• Controller families overlap model years. Earlier applications use NGC variants; later ones include NGC4A, GPEC2 and GPEC2A. GPEC2 appears in 2011–2014 Hemi cars, and GPEC2A includes 2014 truck applications. Neither name alone puts the vehicle outside this page. Read the controller identity and OS from this vehicle before choosing instructions.
• A software heading named Intake Camshaft is a view into a single-cam engine. It is not proof of an independently movable intake cam. The phaser turns the one cam in the block. Both valve-event sets move with it. Treat a table name as a label, not as a second camshaft.

MDS does not follow the engine name. The 6.1 has none in this window. The 5.7 is not universal across every car, truck and manual configuration. The 6.4 has to be checked. The 2014 Ram 6.4 HD with the 66RFE has MDS and Fuel Saver.

Check that powertrain separately from an HD chassis cab with another transmission. The 2014 300 SRT also has Fuel Saver and a five-speed automatic.

The crank turns twice for one turn of the cam. The phaser changes the cam's angular position relative to the crank. Because both the intake and exhaust lobes are ground on the same cam, both event sets move together. There is no separate intake cam to schedule in software.

• Oil pressure moves the phaser. The solenoid controls oil flow, and the duty cycle is a command rather than a position. A duty reading tells you the PCM is asking for something. It does not tell you where the cam is. Actual angle has to come from a position channel or a physical check.
• Determine the unpowered position from the actual phaser part and service data, then verify the installed timing. A channel reading near 120 cannot identify advanced versus retarded on its own. Establish the reference before using that reading to judge a locked or limited cam.

The 2011 limiter instruction describes a startup diagnostic sweep and says the calibration has to be compatible with the phaser hardware. A sweep is a self-check, not a tuning target. If the sweep produces a correlation or performance code after a cam or phaser change, fix the configuration or the mechanical state.

Do not suppress the code to make a mismatch look fixed.

Three numbers get mixed in cam discussions: mechanical travel, software limit and absolute reference. They are not interchangeable. Mechanical travel is how far the phaser can move. A software limit is the range the calibration allows. An absolute reference is the zero point and direction behind the number in the log.

Those travel and retard figures come from a manufacturer instruction for a historical application. They are not a measured stock angle map for every operating system. They do not tell you the zero point in your Scanner.

They do not tell you whether your channel counts crank degrees, cam degrees or an offset.

• The arithmetic is simple and useful. If a position channel in crank degrees reads 120 at one end, a 14-crank-degree move puts the other end at 106 or 134. The direction and the zero point decide which. This is an illustration of convention, not a Hemi calibration. Do not choose 106, 120 or 134 as an endpoint from it.
• For a hypothetical cam card, an intake centerline of 110° ATDC is already measured in crank degrees. Retarding the cam by 4 crank degrees moves that event to 114° ATDC. The camshaft itself rotates 2 degrees relative to the drive. Do not divide the printed 110 by two. A Scanner channel can use a different reference, so this example does not supply its target.
• A 14-degree travel limit does not mean the desired-angle field should contain 14. A lock is not 0 in the position channel. A locked phaser holds the installed reference, and the channel may read any number that corresponds to that position. A limiter restricts travel from the hardware's defined stop; it need not allow equal movement in both directions. Neither device turns the table into an absolute target.

The hardware decision comes before the table. A limiter restricts travel, a lock removes travel, and a stock phaser keeps its original travel. Each needs a different calibration and a different diagnostic expectation.

The COMP 5761CPG limiter allows at most 14 crank degrees of phasing, equal to 7 cam degrees. A matching lock eliminates movement. Those are different hardware choices. A broad 6.1 mention in a limiter listing does not override engine applicability.

• Actual safe clearance can be tighter than the limiter. The cam, installed centerline, piston, head work and spring geometry decide. Degree the cam and check piston-to-valve clearance over the intended travel. Check spring, retainer and pushrod geometry through the engine builder's procedure. A tune cannot create clearance that does not exist.
• Not every cam needs the same hardware. The COMP 201-303-17 has 220/230 degrees of duration at 0.050-inch lift. It requires a limiter or lock and non-MDS lifters with MDS disabled. The MMX 5.7 NTR MDS cam requires MDS lifters and specifies no phaser limiter or spring replacement. Its non-MDS version is a separate part. Both combinations exist. The cam card and the kit instructions decide which case you have.
• A stage name is not a specification. It does not tell you the cam card, the limiter, the springs, the installed centerline or the clearance. The same stage label from two sellers can describe two different grinds. Read the part number and the card, then set the calibration to match.

Tracking is a chain: command, solenoid duty, oil pressure, phaser response, cam position. A break anywhere in the chain gives a large error. The error alone does not name the broken link.

1. Find every control path. Identify the desired-angle surfaces, limiters, enable gates and startup behavior in the actual file. One WOT table does not prove it is the only command path.
2. Restrict the command to the mechanical range. Use the verified reference and unit. Do not copy another file's endpoints. Do not put 14 in every angle field.
3. Log the set. Desired and actual angle, duty, rpm, load, oil temperature and pressure where measured, voltage, and cam and crank codes. The logging guide covers channel setup.
4. Warm the system and start small. Make one reachable command in a low-risk region. Watch the direction and how it settles. Do not command an end stop to discover polarity.
5. Branch on the trace. If desired changes and duty reacts but actual does not, inspect oil supply, the control valve, the phaser and mechanical timing. If desired stays fixed with zero duty, inspect the enable gate, the strategy and the ANN or VVT setting.
6. Compare the error across regions. Check more than one rpm and load point. No universal plus or minus two degree tracking tolerance was found. Use the service diagnostic threshold for the application.
7. Recheck startup, hot restart and codes. A calibration that works cold and fails hot is not finished. Do not suppress a correlation or performance code to make a mismatch look fixed.

As a hypothetical tracking example, desired angle changes from 120 to 116 crank degrees while actual changes from 120 to 119. The requested move is 4 degrees; the measured move is 1 degree. The remaining error is 3 degrees.

If duty reacts, investigate the response and the channel definition before changing the target again. These values illustrate the comparison; they are not endpoints or an acceptable-error threshold.

• Zero duty does not prove a dead solenoid. Control may be disabled or its enable conditions may not be met. A large target-to-actual error does not prove bad mechanical timing. It can come from oil, electrical or hydraulic control. Diagnose the branch before you substitute a value.
• The 2009–10 files have an extra dependency. HP Tuners support documentation describes cases where the neural network and VVT have to be disabled together. Control disable is not a mechanical lockout. If you choose that route, the cam position still has to be safe under every condition.

Start with fuel. A cam move changes volumetric efficiency. A lambda change during a phaser test is not a VVT result. Establish injector data and an airflow model that is valid at each cam position you intend to use. The airflow and fuel guide covers the model side.

• Hold fuel and spark conditions comparable, then make controlled loaded comparisons at mechanically approved cam positions. A two-crank-degree step is a possible test resolution, not a sourced prescription. The step has to be small enough to see the direction and large enough to separate the result from noise.
• Compare actual cam position and torque, not the requested angle. The airflow and fuel guide covers the torque estimate behind that request. Include the rpm the engine lands in after a shift. A change that adds peak power and loses the after-shift pull is a different result. The RFE guide and the NAG1 guide cover the transmission side.
• Build a smooth target surface. Avoid a hunting boundary between neighboring targets. Retrain or revalidate the neural network or direct-VE representation for each position you keep. A single fixed-cam fuel surface cannot represent every moved-cam condition.

Recheck idle, light load, enrichment, spark and knock, and the MDS transitions if they remain. A phaser target that creates a hunt between two cells is worse than a slightly lower torque number that repeats. Smoothness is part of the calibration, not a cosmetic finish.

• A phaser target that is safe at cruise can still be wrong at idle and cold start. Check the actual angle at cold idle, warm idle and the first loaded transition. A cam with more overlap needs idle airflow and spark work, and the phaser position is part of that. Do not chase an idle hunt with the phaser table before the airflow and spark are stable.
• Boost and E85 do not set a universal phaser map. Blower type, backpressure and cam events change the optimum. Fuel alone does not set phasing. The spark and knock guide covers the ignition side of the same loaded test.

A locked phaser is a fixed-cam engine for calibration purposes. The lock removes movement. It does not correct a cam installed one tooth off, and it does not validate clearance.

1. Verify the installed position and clearance. Confirm the lock's actual position against the cam card. Check piston-to-valve clearance over the fixed state.
2. Align the calibration with the fixed state. Set the expected position and the documented control switches. Do not leave a moving-target table active.
3. Preserve relevant fault detection. Handle a configuration-specific diagnostic only with a stated reason. A missing movement command does not validate mechanical timing.
4. Confirm the position warm and cold. A physical lock should hold the same mechanical position. If the reported angle changes after heat soak, check sensing, timing and the lock installation.
5. Make the airflow data describe the fixed cam. Retrain or revalidate the model for the installed position. Do not leave a table built for a moving cam.
6. Revisit idle, startup, load and spark. Check the cold start and the hot restart, then the loaded region and the knock response.
7. Document the tradeoff. Fixed timing simplifies control and loses the ability to move the torque curve. No fixed gain or loss is claimed without a back-to-back comparison.

A locked cam can simplify the fuel model because one position removes a variable. It also removes the phaser's ability to trade low-end torque against top-end power. The result depends on the cam and the rest of the engine. Measure the curve you actually get instead of assuming the lock improved it.

MDS deactivates cylinders 1, 4, 6 and 7 under light load. Each selected cylinder has two deactivating lifters, giving eight MDS lifters and four oil-control solenoids.

A P3400 is a rationality code. The 2006 Charger 5.7 diagnostic description identifies a bank-one lean indication during four-cylinder operation.

Oil is application-specific. The 2014 Challenger fluid table lists 5W-20 for the 5.7 and 0W-40 for the 6.4. Use the engine's own specification.

A generic MDS code does not identify the failed part. Separate an electrical circuit fault from a failure to deactivate and a failure to reactivate. Those are different branches, and a calibration change can make one of them worse.

1. Confirm the hardware and the original configuration. A swapped long block can disagree with the PCM. Record the cam, lifter, solenoid and block-off parts if the engine has been modified.
2. Save the DTCs, freeze-frame and baseline log. Do not clear a code before you record it. The conditions in the freeze-frame are part of the diagnosis.
3. Check oil level, specification and measured pressure. Check misfire, compression and wiring before you blame the calibration. A mechanical fault can look like a control fault.
4. Log a warm light-load region where MDS engages. Use a direct state channel if the OS has one. Otherwise document the uncertainty and compare the related channels.
5. Compare MDS state, converter state, MAP, trims and misfire. A transition and a converter apply can occur close together. A shudder aligned with both cannot be assigned to either by feel.
6. Test cylinder contribution after a return to eight-cylinder demand. Distinguish spark, fuel and compression from a collapsed lifter or a stuck control. A tune cannot restore a damaged roller or cam.
7. Check the transition separately. If the fault appears only during a transition, inspect the electrical command, the oil control and the mechanical response in that order.

Do not copy a code list from another operating system. Circuit numbering and rationality codes differ. Read the target service data and diagnose the exact code. A bulk disable list can hide a circuit fault that still needs a repair.

• If a cylinder remains noncontributing after the engine returns to eight-cylinder demand, the cause can be spark, fuel, compression or a collapsed lifter. A calibration cannot restore a damaged roller or cam. A disable is not proof that the underlying fault has been repaired.
• A knock event that appears only at the MDS handover is not a reason to add spark across the map. Check the transition state and the cylinder contribution first. Then decide whether the timing change belongs to the handover or to the steady-state table.

A tune-only disable is a command change. It is reversible, and it leaves the collapsible lifters and solenoids in the engine. It is a valid choice for an owner who wants the four-cylinder transitions gone. It is not the default for every MDS engine.

It is a calibration choice, not a repair or a hardware conversion.

1. Preserve the as-found file and agree the request. Record why the owner wants the change: drone, transition feel or a hardware plan. A preference is not a diagnosis.
2. Find the master control through the file help and search. Check the advanced parameter view before you conclude that the control is absent. Labels and paths differ by OS.
3. If a documented enable switch exists, set the disabled state. Review the change list. Do not disable unrelated thermal, knock or diagnostic functions.
4. If only operating windows appear, do not call a speed-gate change a complete disable. Establish a supported method for this operating system. Leave the request unresolved rather than fake success.
5. Write with the documented PCM workflow. Follow the prompts, then read back the supported calibration and compare the MDS setting with the intended file. Repeat the original warmed-up engagement condition over more than one drive cycle.
6. Verify a responsive state channel and the surrounding channels. Check for new faults, stable idle and cruise, cam tracking where equipped, and transmission behavior.
7. Keep the hardware present and healthy. A software disable is not a lifter replacement. The collapsible parts remain a service item.

A speed window is not a disable. A minimum-speed change that only moves within a narrow range does not remove highway operation. A single-file report of a narrow minimum-speed limit is not a Mopar-wide rule. If the file exposes only windows, the honest result is a partial change, not a completed disable.

• The 2014 Ram owner's manual warns that Fuel Saver may take time to return after a battery disconnect. Immediate absence after a reset is not proof of a permanent disable. Drive the known engagement route warm and compare the direct state. A later return of MDS shows that deactivation remains permitted. Only a file comparison establishes whether the calibration changed.
• If economy is part of the request, use a matched route, the same speed and the same load, and compare after adaptation. The dash reading is not a measurement.

A mechanical delete changes the hardware, so the calibration has to agree with what is installed. The exact cam, lifter, block-off and oil-gallery requirements come from the kit. Plugs and non-MDS lifters are not created by a checkbox.

1. Use the exact kit instructions. Follow the cam, lifter, block-off and oil-gallery requirements for the parts installed. Do not mix a card from one kit with hardware from another.
2. Preserve the shared wiring. Do not cut the MDS wiring as a disable method. On the 2009–2014 VVT engines that also have MDS, the circuits share a path, and a cut can take the phaser with it.
3. Configure the PCM to stop requesting deactivation. Muting a lamp does not stop a fuel or torque strategy. The calibration has to match the absent hardware.
4. Diagnose remaining circuit or rationality faults. Record which diagnostic behavior legitimately changes because of the verified conversion. Do not hide every related code.
5. Verify the conversion. Check eight-cylinder operation, cylinder contribution, actual cam state, oil condition and pressure, warm cruise, and hot and cold restart.

A smooth first start does not validate the full conversion. The hot restart, the warm cruise and the contribution test are part of the same check.

• One manufacturer sells an MDS-compatible performance cam that keeps the MDS lifters and needs no delete. A different specific cam requires non-MDS lifters and MDS disabled. Neither rule generalizes. Check the part number, the year and the complete kit.
• A tune-only disable does not replace the lifters. No controlled evidence here shows that it stops lifter wear or extends lifter life. State that limit in the delivery note. If the engine is already open for a tick or a cam, the hardware decision is part of the build, and the calibration follows it.

On the 2009–2014 engines that have both systems, MDS and VVT share wiring and calibration context. A mechanical MDS delete on a VVT engine still needs the VVT circuit intact. A phaser change on an MDS engine still leaves the deactivation hardware in place.

The two jobs have to be planned together.

The airflow model has to cover the states you keep. MDS changes the number of contributing cylinders. The phaser changes volumetric efficiency at the same rpm and load. If both remain active, the model and the diagnostics have to describe both. A single fixed-cam, fixed-mode fuel surface cannot represent both.

• Forced induction and E85 do not establish a universal MDS-off rule or a universal phaser map. The kit and the tuner configuration still have to be checked. Low-load behavior still has to be logged. Fuel alone does not set phasing or deactivation.
• The transmission sees the torque result. A cam that moves the torque curve can change shift feel and converter apply. An MDS transition and a converter apply can occur close together. Validate the pair on the road, not on a table.

Validation is a set of repeated conditions, not one drive. Cold start, warm idle, light-load deactivation, a phaser step, a loaded pull, a shift and a hot restart each answer a different question.

1. Baseline warm and save the files. Record the OS, the hardware, the oil and the exact conditions. The getting started guide covers the read and save.
2. Change one thing. Change a cam position, an MDS control or a target surface. Do not change all three in one write.
3. Repeat the same route. A different road, tire pressure or load is a different test. Use the same conditions for the comparison.
4. Compare command and actual. A command that moved and an actual that did not is a different problem from a command that never changed.
5. Check MDS and VVT separately, then together. A stable phaser with a bad transition is not a finished combination.
6. Send the package for review. Include the file, the log, the channel config, the IDs, the modifications, the oil and the exact changes. No VIN or customer name on a public example.