No matter what type of vehicle you’re proud of owning and driving, it’s always fun to talk numbers with like-minded enthusiasts. But those numbers can’t be known for sure unless a vital tool is brought to bear: the dynamometer.

Dynojet Research has made these valuable products for over 40 years, and along the way made it possible for diesel guys and girls to find out what their trucks are generating in terms of power and torque. We had a chance to talk with Will Fong and find out what were the most poignant questions from this crowd.

The best way to get an RPM reading on a diesel is by using the Optical RPM, which works with reflective tape on the harmonic balancer along with a magnetic base and adjustable arm with a sensor.

The first question was about how to get the engine’s RPM signal – what is the best method? “Our standard way of getting RPM is by using an inductive RPM clamp/cable to clamp over a spark plug or ignition wire source,” said Fong. “For diesel engines, the most reliable way to get the RPM is to use the Optical RPM. It uses reflective tape placed on the balancer along with a magnetic base and adjustable arm with a sensor.”

Alternately, recent developments have made it possible to get a reading through the OBD-II port on a truck. “We make a module for 2008 and newer CAN ECMs that use the engine RPM signal as the signal source. The EZ-RPM is another option that plugs into the cigarette lighter or on the battery. A secondary inductive is used to clamp over a bar on the EZ-RPM.”

The second question relates to boost – how to get an input? For that, the DynoWare RT Main Module is the answer. “The module comes standard with four -5V analog inputs,” said Fong. “We offer Analog Cable Kits for using these channels with three options: a plug-and-play -14.7-to-45psi pressure sensor, a plug-and-play 0-100psi pressure sensor, and a cable kit with non-terminated ends for attaching to customer supplied sensors. Using any of these methods lets the dyno user view real-time boost, fuel, or oil pressure, and then graph it along with power and torque.”

Finally, the last question relates to how to pre-load the dyno – do you need eddy-current load? “Depending on the diesel engine and boosted power output, a diesel truck on a non-load dyno such as the older 248 or the newer 224x , the truck may be able to achieve proper boost pressure with no additional load added during the dyno run,” said Fong. “The older 248 sometimes came with proportional air brakes which can do the job.”

Need to view oil, fuel, or boost pressure? Dynojet makes Analog Cable Kits that let users view readouts as they correlate with

In cases where the dyno cannot provide enough resistance to trigger the turbocharger, the answer is the 224xLC, which can add extra load. “It is the ideal solution,” said Fong. “This is because it has a torque cell that, when calibrated before use, records the loaded dyno run accurately. The 248 prop-air system doesn’t offer that since it could only bring the boost pressure up, release it, and the sample the dyno run.”

For more information on Dynojet’s products and how they can benefit your vehicle, head to the company’s website and Facebook page.