Description
5.7L & 6.4L HEMI PCM Bench Tune — MDS Off, Speed Limiter Removal and a 91 or 93 Octane Performance Tune
A complete mail-in PCM bench tune for every 5.7L and 6.4L HEMI, built by N2 Speed in Pompano Beach, Florida. You choose what you want switched off and which octane you actually pump, we write the calibration directly to your module on the bench and ship it back. You never buy a tuning device, you never pay for a license, and you never plug anything into your OBD port.
No Expensive Tuning Tools Required
The normal route to a tuned HEMI costs hundreds before anyone touches your calibration: an HP Tuners MPVI interface plus credits, or a Diablosport device, or a locked 2015+ PCM that needs unlocking before a handheld will even talk to it. A bench tune skips all of it.
- No tuner device to buy — nothing to purchase, register or resell afterwards
- No credits or licence fees — no per-vehicle VIN charges
- No unlock required first on 2015+ GPEC2A modules — the bench reads and writes it directly
- No laptop, no cables, no software to learn — you ship a module, you get a tuned module
- Nothing to go wrong in your driveway — no failed flash, no bricked PCM on a dead battery
For most owners this is the cheapest legitimate way to get a genuinely custom HEMI calibration.
Fast Turnaround
Most modules are tuned and back in the mail within 24 to 48 hours of arriving. We do not sit on modules waiting to batch them — yours goes on the bench, gets written, gets checked and goes straight back out. Ship it Monday and in most cases it is on its way back to you by Wednesday. If we ever see something on your module that needs a conversation first, we call or email you the same day rather than letting it sit.
Choose Your Options at Checkout
- Performance tune octane — select 91 octane or 93 octane. This is the single most important choice on this page. We build spark and fuel around the fuel you actually run, so tell us the truth: a 93 file on 91 pump gas pulls timing and can rattle, and a 91 file on 93 leaves power unused.
- MDS — MDS off (recommended) or leave cylinder deactivation active.
- Speed limiter — remove the factory top speed limiter or leave it stock.
- 2015+ GPEC2A PCM unlock — only needed if you also want to flash your own files later with a handheld. The bench tune itself does not require it.
What the Performance Tune Actually Changes
- Spark advance optimised for your selected octane, with knock protection left intact
- Wide-open-throttle fuelling targeted for power and safe air/fuel ratios
- Electronic throttle mapping — factory tip-in delay reduced for a sharper pedal
- Torque management reduced where the factory pulls power during shifts and launches
- Transmission shift firmness and shift points tidied up where the PCM controls them
- Rev limiter and speed limiter set per your selections
- Cooling fan and closed-loop strategy reviewed so nothing fights the new calibration
Typical result on a stock or lightly modified HEMI: a noticeably sharper throttle, stronger mid-range pull and better shift quality. A naturally aspirated HEMI on pump gas is not going to gain 100 horsepower from a calibration and we will not pretend otherwise — what you get is the engine finally running the way it should have from the factory, without MDS or a speed limiter in the way.
Why Delete MDS
Chrysler's Multi-Displacement System shuts down four cylinders under light load to save fuel. Owners pay for it in other ways:
- Rough idle and vibration when the engine drops into four-cylinder mode
- Premature lifter and camshaft failure — the well-known HEMI tick, a genuinely expensive repair
- Inconsistent power delivery when merging or passing as the system cycles
- Check engine lights from failing MDS solenoids
Switching MDS off keeps all eight cylinders live at all times. It is the single most common request we get on the bench, and the reason a lot of owners tune a completely stock truck.
Fitment — 5.7L and 6.4L HEMI
- 5.7L HEMI — Dodge Charger, Challenger, Magnum, Durango; Chrysler 300 and Aspen; Jeep Grand Cherokee and Commander; RAM 1500, 2500 and 3500
- 6.4L 392 HEMI — Charger and Challenger Scat Pack, R/T Scat Pack and SRT 392; Durango SRT; Jeep Grand Cherokee SRT and Trackhawk-platform 392 applications; RAM 2500 and 3500 6.4L
- Supported modules — NGC3, NGC4, GPEC, GPEC2, GPEC2A
- Years — roughly 2005 through 2024 depending on model and module
Not sure which PCM is in your vehicle? Send us your year, model and a photo of the module label at sales@n2speed.com and we will confirm before you order.
How It Works
- Order here and pick your octane, MDS and speed limiter options.
- Remove your PCM and ship it to us with a copy of your order confirmation.
- We tune it on the bench — written directly to your module and verified before it leaves.
- We ship it back within 24 to 48 hours of arrival. Reinstall and drive.
Ship to: N2 Speed
1461 SW 30th Ave. Bay 16, Pompano Beach, Florida 33069
Use UPS or FedEx with tracking and insurance. Pack the module so the connectors are protected.
Important Notes
- This is a mail-in bench service. Your vehicle is down while the module is with us, so plan for it.
- Tell us your real modification list and octane. A calibration written for the wrong fuel is the fastest way to hurt an engine.
- Modified calibrations are intended for off-road and racing use where emissions rules require it, and can affect your factory warranty.
- No refunds once your module has been tuned and shipped back.
Related Services
- MDS delete and speed limiter removal only — if you do not want a performance calibration
- All Dodge PCM bench tuning services
- PCM bench tuning — how it works
- Dodge, RAM and Jeep PCM / TCM unlocking
Questions before you ship? Call (954) 406-8550 or email sales@n2speed.com. N2 Speed — Pompano Beach, Florida.
