Dynamometer Services

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The main difference between a Dyno Dynamics and a DynoJet is that the Dyno Dynamics is a load-bearing dyno. Follow this link to a write-up on the load-bearing dyno by tuning guru Greg Banish http://www.calibratedsuccess.com/AboutUs.htm.

A load bearing dyno (e.g., Dyno Dynamics) gives the calibrator the ability to hold the engine at one location while he refines the map of the surrounding area. Inertia only dynamometers (e.g., DynoJet) freely accelerate as the engine makes more power. This makes it difficult to hold the engine steady at all the necessary map locations and build a detailed map. Load bearing dynos have the ability to hold the engine steadily in a much wider range or map locations in order to properly tune these areas. The more accurate these measurements can be at each point, the smoother the engine will run. So a dynamometer that can allow the tuner to make accurate measurements at each individual point on the map gives him the potential to make the engine run smoother in these areas as well. Keep in mind that this applies not only to fuel delivery, but the spark map as well. Finding MBT timing at part throttle requires instantaneous torque feedback at steady state that can only be done with a properly load controlled and instrumented dynamometer.

The added benefit to a load bearing dynamometer is that when it comes time to test dynamic conditions, the rate at which the engine sweeps across the RPM range can be adjusted to match exactly what happens in the real world. This means that the amount of time it takes to complete a run is the same between the track and the dyno. We have a better idea of just how much heat and load the engine will see on the street or track.

The Dyno Dynamics dynamometer is known as the "heartbreaker" dyno because it gives lower numbers than dynojets. There is a lot of theory and an even greater amount of internet debate into why this is the case. Since I am no expert on the matter I will refrain from attempting an explanation. Ultimately one must realize that a dyno is a tool used for tuning cars and that the load-bearing dyno allows greater flexibility in this regard. I have come to understand that variation in numbers should be expected between all the different dyno types. If you want to compare torque and horsepower numbers I personally think that your best bet is to run the cars on the same dyno on the same day and see how they compare.

Ultimately if you are really interested in learning about dynamometers and tuning, I suggest that you sign up for the EFI 101 class we are hosting. The instructors from EFI University are the real guru's in this regard and should be able to provide a more complete answer.