The Power Of Testing
When it comes to making the most of any engine build, there is little that can substitute for empirical testing-that is running the numbers in search of the optimal combination. Not so long ago, real test data was relatively thin, with only a select few shops being equipped with dyno test equipment. Decades ago, dynos were bare-bones devices, with little in the way of data, often just a torque gauge with no means of recording information. We've come a long way since then, with computerized dynos capable of recording many channels of data, as well as the capability to derive a myriad of calculated data. More importantly, the cost of dyno equipment has become affordable enough to make owning one a viable consideration for a serious engine shop. Even for the casual engine builder, finding a reliable dyno shop and using it is the sure way to sharpen your game.
Testing is an all-important part of competing in the Engine Masters Challenge. Clearly, testing at the event is how we determine the winner, but what I am referring to here is the behind-the-scenes testing that backs up any serious entry. Any competitive engine starts with a plan, and that is usually based on the builder's experience, know-how, and ideas. This is the starting point. What follows is putting these ideas to the test, and that involves dyno time. From speaking to the top-finishing builders at the Challenge, we've found that testing and development time is what will make or break a competition effort.
So what is involved in the testing aspect of an Engine Masters engine? The object here is to do what it takes to make the engine better. As with the initial build stage of the game, what's done in testing will depend upon the builder's knowledge and experience, making changes and adjustments to optimize engine performance. A successful testing regime is much more refined than simply throwing darts at the wall and seeing what sticks. Using the data, a skilled engine builder can see areas where the engine needs improvement, and using theory and experience, make changes to try and make gains. For instance, a builder looking at the data might see an area in the power curve that needs work. Depending upon the specific problem, changes might include altering the cam timing, port size, runner length, or changes to the header design. The knowledgeable builder will look critically at the current combination and dyno numbers, weigh that against theory and previous experience, and make specific changes accordingly. These changes may or may not work, but the dyno will act as an impartial judge and help point the way to improvements. As PHR contributor, David Vizard, often says, "I don't have an opinion, I've got a dyno."
While the dyno can help a builder refine a given package, it can be a critical tool in component selection. We had a successful builder in last year's challenge who spent extensive dyno time testing a huge assortment of header and collector designs. This is a case where it is very difficult to predict just how the engine will respond to a specific change, so the process involved a great deal of trial and error, and learning the trends of how the engine responds to the various configurations along the way. Another example of using the dyno to define and quantify changes was related to us by a builder who actually altered the intake port and manifold runner size on the dyno to gauge the effect.
It's well evident that dyno testing is a vital aspect of developing an Engine Masters Challenge engine, but it can also be a big help in developing your own engine project. While most enthusiast normally do not have access to the amount of dyno time some of our professional builders do, a dyno test can help narrow component selection to better your own build.