Dyno Mighty!

We have an amazing dynamometer laboratory at Racing. The lab is how we know you’re getting the performance and durability you expect. It is independently certified to International Standards Organization (ISO) requirements. Each day, our dynos are put to work: verifying production engine output (video below), validating components, improving quality, reducing emissions or developing power. Although a dyno is helpful for production consistency, it’s indispensable for development. Our engineers and technicians have logged hundreds of thousands of hours conducting dyno testing. They’re pretty good at it.

Moreover, ours is the only lab in the world that can certify exhaust gas emissions on spark-ignited engines over 1,000 hp. Erik Christiansen, our Engineering Director, searched the world to find someone to do emissions testing for us. No one could, so we built our own capability. We are making engines both cleaner and more fuel efficient. We understand dyno processes.

Corrected power and torque as captured with Racing’s ISO 3046-1 measurement process.

I’ve seen some very misleading dyno demonstrations by others – usually trying to sell something to us, or to you. The most egregious is claiming power with a ten-second dyno sweep. There is a right way: Standards organizations like ISO and the Society of Automotive Engineers (SAE) require enough run time at each data point for engine temperatures and pressures to stabilize. Depending on the engine, dyno set-up and test process, stabilization can take from 30 seconds up to a minute at each point. These “heat soaked” points are then adjusted to standard temperature, barometric pressure and humidity – reported as “corrected” torque and horsepower. It takes almost a half hour to generate an honest, reproducible power curve. That’s time well spent for development. It works best for comparisons made on the same dyno, under similar conditions.

The result of our knowledge is something you can feel. Today, most of our engines manage boost pressure themselves, using on-board computers. For six years, Racing’s pressure charged engines (both SCi’s with screw compressors and our new QC4v twin turbo) have had algorithms that manage air flow (and therefore power). They are self-correcting to the real boating world. But, how?

These engines measure actual atmospheric conditions in this 46 Cigarette’s engine compartment. They adjust automatically to maintain 1350 hp apiece.

Erik’s engineers establish operating targets: We look at conditions in an engine compartment on an average day and set a baseline. When the propulsion control module (PCM) senses actual airflow in the engine is other than expected (due to warmer air or high altitude, for example), the control system changes boost (airflow) to compensate.

A 1350 for MTI after 75 minute break in and 30 minute  dyno performance verification. For every engine from Racing, this is the last step of production prior to shipping.

That makes consistent boat performance, but can confuse a hapless dyno. Also, correction to “standard conditions” is less straightforward (or downright puzzling to some folks) because a Mercury Racing engine has already adjusted itself to typical under-hatch conditions. If dyno supply air is cooler than the engine room norm – and it almost always is – the engine will cut back its own power to compensate. Fortunately, Racing’s sophisticated dynos keep it all straight and, with heat soaking before data collection, data is reproducible. You’ve had a glimpse of our engine logic and dyno process. Now, in your boat…

As good as our dyno-based boat load simulations are, a dyno is not a boat. What matters to you (and me) is observed power. Because of our PCM algorithms, Mercury Racing engines deliver in-the-boat performance with the temperature, pressure and humidity of your day on the water. Tens of thousands of high performance boaters love our results! My favorite text message so far this year: “Holy @%#! Faster than race boat. When can we have them?” Now you know why: Observed power is power to win!

Share Share

Leave a Reply

Your email address will not be published. Required fields are marked *