One of the best ways to measure the pure performance of your car is on a dyno. I say this because you remove the human element. While I love doing track days, I’m not an amazing driver. So to measure lap times would not only take into account the engine performance and suspension setup of the car, it’s also factoring in my driving abilities.
So what is a dyno?
I’m referring to a chassis dyno in this thread. A chassis dyno uses a set of rollers that allows you to basically drive in place. This helps you tune the car’s ECU (computer) while stationary. There are two main types of chassis dynos that you can use:
- Inertia Dyno
- Brake Dyno
The inertia dyno is going to typically generate a 15-20% higher number than the Brake dyno because it lacks the resistance. Using a brake dyno allows you to dial in your tune much more accurately because you can control the load, but because it has some resistance by design, it won’t produce as high of a number on a WOT pull.
I don’t claim to be an expert on dynos, but I have tested my car on four different dynos:
- Mustang Dyno
- Dyno Dynamics (2 different dynos here)
- Dyno Jet
The important thing to remember is that not all dynos are the same. Not only are they manufactured differently, but with a few clicks of a mouse it’s possible to adjust settings like SAE to produce a different number as a result. Your best option is to find a dyno and tuner you trust and measure your performance on the same setup each time you do an upgrade vs. trying your setup on different dynos.
If you would like to read more about Dynos, check out this wikipedia page: en.wikipedia.org/wiki/Dynamometer
If you’re looking for a quality tuner in the Midwest, check out Dynosty.
Finally, I would like to point out that it is my opinion (and I’m not alone on this) that a properly setup brake dyno (like a Dyno Dynamics) will yield more accurate results for tuning and lower HP numbers when compared to an inertia dyno (like a Dyno Jet). This doesn’t mean the Dyno Jet is bad, but it’s very hard to compare these two because they are apples and oranges. At the end of the day, the only way to compare two cars is to put them on the exact same dyno with the same weather conditions… Or take the cars to the track!