Our Dynamometer

Late Model Domestics (LMD) utilizes a Mustang Chassis Dynamometer, which is a significant choice for a high-end performance shop. In the tuning world, Mustang Dynos are often referred to as "Heartbreakers" because they tend to show lower, more realistic horsepower numbers compared to the more common "inertia" dynos like a Dynojet.

Load-Based Testing (The "Mustang Dyno" Difference)

Unlike an inertia dyno that simply measures how fast you can spin a heavy drum, LMD’s Mustang Dyno is load-based. It uses an eddy current power absorption unit to simulate real-world driving conditions, such as wind resistance and the actual weight of the vehicle.

  • Why it's better for tuning: It allows the tuner to hold the car at a specific RPM and load. This is critical for dialing in part-throttle drivability, not just wide-open throttle (WOT).

  • Real-World Accuracy: Because it simulates the road, the tune you get on the rollers at LMD will translate much more accurately to how the car feels on the street/strip.

Drivetrain Capabilities

LMD’s facility is equipped to handle the most powerful late-model platforms:

  • RWD & FWD: LMD specializes in high-horsepower Rear-Wheel Drive (RWD) platforms like the Hellcat, C8 Corvette, and Mustang.

  • High Horsepower Handling: The Dyno setup is designed to handle builds exceeding 1,000+ WHP, making it the go-to spot for twin-turbo or big-blower builds.

Results

When you get a custom tune at LMD, you aren't just getting a "feel-good" seat-of-the-pants adjustment. LMD’s dyno services provide:

  • Precision AFR Monitoring: Real-time Wideband Air/Fuel Ratio monitoring to ensure your engine stays safe under boost.

  • Boost & Vacuum Data: Integrated logging to check for belt slip or boost leaks during the pull.

  • Documentation: Every performance package includes a printed dyno graph and video of your car’s run, which is great for your own records or for resale value later.

Dyno Service at Late Model Domestics

  • A Dyno Pull is the baseline "health check" of the performance world. While a full tune involves rewriting software, a dyno pull is a diagnostic session used for verification.

    Verification isn't just about the peak horsepower number. Professionals look at the graph architecture and sensor data to verify three critical things:

    • Air-Fuel Ratio (AFR) Verification: A "wideband" oxygen sensor is placed in the tailpipe or a bung in the headers. It verifies that the engine isn't running "lean" or too "rich"

    • Power Curve Smoothness: A jagged line on the graph indicates a problem—usually spark blowout, fueling inconsistencies, or the ECU pulling timing due to "knock" (pre-detonation).

    • Drivetrain Loss: Since LMD uses a Mustang Dyno, they verify "Wheel Horsepower", which accounts for the energy lost through the transmission and differential. This is the most honest way to verify how much power is actually hitting the pavement.

      • The "Before and After": If you are doing a build in stages at LMD, you may want do a baseline pull before adding parts.

      • Safety Assurance: If you bought a car that was already modified, a verification pull is the only way to know if the previous owner’s tune is safe.

      Dyno Operation

      • Setup & Strapping: The car is secured to the rollers using high-tensile ratcheting straps. For high-horsepower cars like a Hellcat or ZL1, shops often use "over-the-axle" or "chassis-mount" strapping to ensure the car doesn't "walk" or climb off the rollers at 150+ MPH.

      • The Pull: The technician accelerates the car through the gears to a 1:1 ratio (usually 4th or 5th gear) and then performs a wide-open throttle (WOT) sweep from low RPM (e.g., 2,500) all the way to the redline.

      • Cool Down: Between pulls, large industrial fans are used to simulate high-speed airflow, keeping engine temperatures stable so the data remains consistent.

  • At Late Model Domestics (LMD), custom dyno tuning is the use of software that controls the high-performance hardware installed. While many shops use "canned" tunes, LMD specializes in in-house calibration, meaning the person writing the software is the same person physically operating and observing the car's behavior on the rollers.

    Drivability Matters

    Mario and the LMD team emphasize that a "peak number" means nothing if the car is not enjoyable to drive.

    • Partial Throttle Mapping: LMD spends a significant amount of time on the Mustang Dyno adjusting the airflow and fueling for 10% to 50% throttle. This ensures your 800 HP Hellcat or C8 Corvette still feels smooth and responsive at a stoplight.

    Safety Margins: LMD tunes are built with "real-world" safety. They account for the high humidity of the current environment and quality of local pump gas.

    Supported Platforms & Software

    LMD uses industry-standard tuning suites and have specialized knowledge in the proprietary logic of modern ECUs for GM, Ford, and Mopar.

    • Mopar (Dodge/RAM/Jeep): LMD Dyno operators are experts in HP Tuners and are one of the few local shops that handle the full PCM unlock, security gateway bypass, and TCM (Transmission) tuning for the 8-speeds.

    • GM (Chevy/Cadillac): From Gen 4 LS engines to the complex, encrypted E99 ECUs in the C8 Corvette and CT5-V Blackwing.

    • Ford: Specialized tuning for the Coyote 5.0 (S550 and the new S650 platforms) and the EcoBoost Raptor/F-150.

    Advanced Tuning Features

    LMD doesn't just "flash a map"; they architect custom logic into your vehicle's computer:

    • Flex Fuel / E85 Calibration: They can install and tune for DSX Flex Fuel sensors, allowing your car to automatically adjust timing and fueling based on the ethanol content in your tank.

    • Transmission Tuning (TCM): For modern automatics, they recalibrate shift points, shift firmness, and torque management. This is often just as important as the engine tune for improving 0–60 and quarter-mile times.

    • Boost Control: For their ProCharger, Whipple, and Magnuson supercharger packages, they precisely manage boost bypass and timing curves to prevent heat soak.

    The Tuning Experience

    When you book a custom tune at LMD, you aren't just dropping off a car; you're getting a documented performance transformation:

    1. Pre-Tune Inspection: They check for boost leaks, vacuum leaks, and mechanical health before the car ever touches the rollers.

    2. Iterative Calibration: Multiple pulls are made to "walk" the car up to its final power level safely.

    3. The Deliverables: You receive a printed dyno graph and a video of the final pull.

    4. Ongoing Support: Many customers highlight LMD’s "open communication," providing updates and answering technical questions.

  • While Late Model Domestics (LMD) is primarily known for their full-service performance packages, they do offer Dyno Rental services for enthusiasts who need professional-grade equipment without necessarily needing LMD’s full tuning suite.

    Renting LMD’s Mustang Chassis Dyno is a strategic move if you are working with a remote tuner or if you’re a hobbyist calibrator who needs a controlled, load-bearing environment.

    Why Rent the LMD Dyno?

    Most dynos in the area are inertia-based (like a Dynojet), but LMD’s Mustang Dyno is load-based. This is a major advantage for rental because:

    • Remote Tuning Support: If you have a high-end tuner (like a remote specialist in another state) who needs to log data, LMD’s dyno allows them to "hold" the car at specific RPM and load points.

    • Safety & Stability: The dyno is designed for 1,000+ HP builds. Renting a professional session means you get the industrial cooling fans, wideband oxygen sensors, and safety strapping required for high-speed pulls.

    • Diagnostic "Clean Runs": If you’re chasing a ghost in your build—like a mid-RPM stumble or a fuel pressure drop—renting the dyno for an hour allows you to reproduce the problem safely away from the street.

Dyno Authorization Form