The Mopar HEMI is one of the most rewarding platforms to build, and one of the most misunderstood. Late-model Dodge, Chrysler, Jeep, and RAM computers ship locked from the factory, so plenty of owners bolt on parts and never see what the engine can really do. At APA Custom Shop in Queen Creek, we unlock the ECU, tune it on our in-house Dynojet, and build your HEMI in stages that actually work together, from a first tune all the way to a full forced-induction combination.
What We Build for the Mopar HEMI
We work across the HEMI family, the 5.7L in trucks and cars, the 6.4L 392 in Scat Pack and SRT builds, and the supercharged 6.2L Hellcat, along with the Chargers, Challengers, Durangos, Grand Cherokees, RAM trucks, and 300s they live in. Whether your goal is a stronger daily driver, a weekend street car, or a dedicated track build, we spec the combination around your car and how you actually drive it.
Everything happens in-house, so your build is not bouncing between shops. From a first ECU tune to cams, headers, forced induction, and full engine work, we handle the parts, the fabrication, and the calibration as one project.
- ECU unlocking and custom tuning with HP Tuners on our in-house Dynojet
- Cam packages spec'd for your HEMI and its supporting valvetrain
- Long-tube and shorty headers plus high-flow exhaust
- Supercharger and turbo installs with supporting fuel system
- Engine builds and swaps, from refreshed short blocks to stroker combinations
- Custom fabrication, plus suspension, brakes, and alignments to match the power
Why a Mopar Tune Starts With ECU Unlocking
Here is the honest part, many late-model Mopar PCMs are locked from the factory, which blocks aftermarket tuning until they are unlocked. Until that is done, even great bolt-on parts run on a calibration that has no idea they exist, so you leave power and drivability on the table. We handle Mopar ECU unlocking so your Charger, Challenger, Durango, Grand Cherokee, 300, or RAM can take a real custom tune.
The exact steps depend on your year and platform, and we will walk you through what your vehicle needs before anything is written. Once the ECU is open, we tune with HP Tuners and verify every calibration on our in-house Dynojet, reading real air-fuel, timing, and knock under load instead of loading a generic file and hoping.
The Package Idea, Tuning to Bolt-Ons to Boost
The smartest HEMI builds happen in stages, where each step supports the next instead of fighting it. You do not have to do it all at once, and you do not want to add boost to a combination that was never set up to handle it. We lay out a path so your money goes toward parts that build on each other.
Because every HEMI and every goal is different, we quote gains and parts for your exact car rather than promising a number off a chart. Ask about current options for your platform and we will tell you honestly where the real returns are.
- Stage one, tuning and intake, unlock the ECU and dial in a dyno tune to wake up the factory hardware
- Stage two, cam and headers, add airflow and that signature HEMI idle, then retune to match
- Stage three, forced induction, supercharger or turbo with supporting fuel and a full custom tune
- Supporting work as needed, fueling, cooling, clutch or converter, brakes, and suspension so the car can actually use the power
Built, Tuned, and Quoted for Your Exact HEMI
No two HEMI builds leave our shop the same, and that is the point. We spec the combination, do the fabrication and installation in-house, and finish every package with a verified tune on our Dynojet so you know exactly what your car makes and that it will live there.
Ready to build your Mopar the right way? Call APA Custom Shop at (602) 762-4916 to talk through your car, your goals, and your budget, and we will quote your exact build, from a first unlock and tune to a full forced-induction combination.