MMX DYNO ROOM NOTICE

Understanding Temperature & Power Differences

At Modern Muscle Xtreme, we use our SuperFlow Engine Dyno and Dynojet Chassis Dyno to provide accurate, repeatable horsepower and torque data. However, even with advanced SAE/STD weather correction, ambient temperature plays a major role in real-world power.

Why Cooler Air Makes More Power

Cooler air is denser, meaning more oxygen per cubic foot. More oxygen allows more fuel to be burned, creating more energy. The engine runs more efficiently with cooler intake charge temperatures.

Why Hot Weather Reduces Power

Even though the dyno applies correction factors, it cannot fully offset how heat affects engine performance: Higher intake temps = less oxygen density Heat-soaked intercoolers and manifolds reduce efficiency ECU knock control may pull ignition timing in high heat Humidity displaces oxygen in the intake air These factors cause real-world power differences that cannot be fully “corrected” by software.

Cooler air = denser charge = more power

Hotter air = thinner charge = less power

Even with SAE correction, you can expect a 15–20 RWHP swing between a cold December pull and a hot July pull. That’s completely normal — and a sign that your dyno and tune are consistent and reacting properly to physics.

DYNO NUMBERS AND COMPARISONS

Every dyno is different — even among professional shops. Power numbers from different dyno brands, software versions, or operators cannot be compared directly. At Modern Muscle Xtreme, we use both a SuperFlow Engine Dyno and a Dynojet Chassis Dyno, each calibrated to provide consistent, repeatable results within our facility. However, results can vary significantly depending on: Dyno Brand: Dynojet, SuperFlow, Mustang, Mainline, etc. all use different load calculations and correction algorithms. Dyno Type: Eddy-brake (load-based) vs inertia-based dynos measure power differently. Operator Input: Ramp rate, strapping method, tire pressure, gear choice, and fan setup all affect readings. Environmental and Calibration Differences: Barometric calibration, tire temperature, and even software versions influence output. Because of these variables, numbers from one dyno cannot be directly compared to another. What matters most is consistency on the same dyno, showing your gains before and after tuning under identical conditions.