Dyno testing is important to measure an engine’s horsepower and torque. At Sterling, the SuperFlow SF-7100 dynamometer is used to accurately test an engine’s power. There are many brands of dynamometers capable of measuring power at a car’s wheels like the “Dynapack” or “Dynojet,” but Sterling opts to use one with accuracy repeatable at or below 1 percent, often around .3 percent. In a racing application, this is the difference in just a few horsepower/torque when testing air-fuel ratios or engineering intake/exhaust parts. Sterling also uses the newer “Black Widow” dyno from Superflow. Read the article below to learn more about the SuperFlow SF-7100 and an individual’s experiences with it over the course of many years in an automotive application.
Manufacturers of test equipment use different standards and test procedures that will affect the results. You need some type of gauge, and engine dynamometers are the ruler used. Flowmaster has had a SuperFlow SF-7100 engine dyno since 1993, and it’s been my toy since 1988. This dyno was state-of-the-art back then and used the latest in computer controls, temperature controls, and the latest correction factors to create very repeatable numbers. When testing exhaust components we are sometimes looking for numbers as small as 1 or 2 hp. You can check with any engine-dyno manufacturer and they will tell you that an acceptable repeatable is at or below 1 percent. Well, as the power levels increase, that 1 percent can be a very big number. Through refinement we were able to hold the repeatable of our dyno to 0.3 percent.
Well, time marches on, and dyno technology does too. Our SF-7100 used electronics that were designed back in the early ’80s, and it was starting to give us trouble from time to time. SuperFlow released its SF-902 system several years ago with complete NSE (new-style electronics), a completely digital data-logging and control system. This is a major advancement from the old analog controls. SuperFlow makes an electronics package to upgrade the 7100. It’s tough to beat the hardware of the 7100, and the new electronics brings us right into the 21st century. With this comes a whole new set of testing parameters and computer controls that takes the operator out of the testing loop. This is where I had a little trouble. Turning the controls over to a computer after having run engine dynos for over 20 years, I wasn’t very happy. This is one of the ways that SuperFlow has been able to raise the level of repeatability of their engine dynos. It takes the operator’s opinions and decisions out of the picture. It brings the engine up on load and to full-throttle the same every time. You basically turn the engine over to a computer. For an old dog that can be very tough. What do you mean a computer knows how to run an engine better than I do?