Most gearheads are about the numbers: how much horsepower their car makes at the crank or the rear wheels. For some, it’s all about the bragging rights, while for others it can be about the difference between a baseline reading and seeing the improvement after a performance upgrade has been installed. Either way, the horsepower and torque seem to be what most people think about when they hear: “dyno run.”
But chassis dynamometers have come a long way over the past couple of decades. While many people may think that a dyno is just about finding how much power a vehicle makes, they can actually help simulate real world driving conditions – without ever leaving the shop. Our own Dynojet Research 224xLC dynamometer is great for getting the numbers, but we use it for much more than just bragging rights.
While performing sound testing with cold air intake systems, we’re able to run a vehicle up to speed in a loaded state to measure the sound level of an exhaust without having to drive the car down the road. This type of testing eliminates wind and road noise so we can get a true sound level reading from the exhaust. Performing sound testing like this is much more convenient when you have a chassis dyno.
However, many tuners will use a chassis dyno to help properly tune a vehicle, whether it’s carbureted or fuel injected. While many carburetors are ‘ready to run’ right out of the box, there are so many variations with regards to engines and components that a chassis dyno is where you can properly tune a carburetor for your specific vehicle.
This allows you to get the optimum air/fuel ratio, as well as seeing where the car might be running rich or lean throughout the run. For an EFI system, we can also see where the numbers lie, and for laptop-tuned fuel injection systems it helps us to map the fuel curves to get the best power and efficiency from the engine.
Where the chassis dyno really helps to tune a vehicle, though, is when we can actually simulate a load on the vehicle, rather than just spinning the rollers and revving the engine for peak gains. You can’t properly tune an engine without a load on the drivetrain, so the chassis dyno allows you to get those real world conditions right there in the shop.
The Eddy Current load control provides a way to replicate certain trouble areas that the car owner may be having – whether it’s off idle, at higher RPM, or even cruising. When we do performance tunes and we want to see how the vehicle will perform when a load is applied, such as climbing a grade, the 224xLC provides the ability to do that as well. Additionally, our dyno can read just about anything that an OBD-II port can provide.
Because the Dynojet can be upgraded, some of the latest in technological advancements can be incorporated into the software. The addition of Dynojet’s DynoWareRT module to all of its chassis dynos opens up a world of options for Dynojet owners. Dynojet’s Will Fong told us, “This upgrade offers multiple expansion ports so upgrading to future capabilities won’t be an issue.”
The display screens are customizable, so if you want to read the load, AFR, torque, engine speed, wheel speed, and horsepower on the same screen, it can be done. The software also allows the user to manipulate the size or location of each gauge on the screen. So if the technician is searching for specific information to tune a vehicle, those parameters can be put up on the screen during the run.
After the run, the technician can view on the dynograph only the specific information that is needed, or all of it, represented by a different color on the chart. This enables us to see where the vehicle performed at its best throughout an entire spectrum of readings, as well as how it was reacting to different conditions such as engine temps, ambient air temperatures, different loads, etc.
The next time you hear someone talk about rear wheel horsepower, just remember that with all of these features and add-ons for our Dynojet dynamometer those numbers could be just a little better if the vehicle is properly tuned. Check out our Dyno Testing 101 video below, and visit the Dynojet Research website for more information on the various styles and options for chassis dynamometers.