The landscape for building and evaluating circle-track engines is on the verge of new opportunities to incorporate some updated thinking. What does that mean? In reality, several factors come into play. Let's examine a few of them that may apply to us of the engine contingency.

Arguably so, chassis-minded circle track racers often advance the belief that power is power and it's an ability to put it on the track that counts. And, from many perspectives, that's a valid viewpoint. But in the background of we who are continually looking for ways to improve engine performance, there's a growing concern about and interest in making "efficient" power, for various reasons. It could be class rules that limit piston displacement or the allowable selection of power-enhancing components. Possibly a "spec" fuel is required. And the list continues. Further, within such restrictions, engine builders not only seek ways to circumvent or "interpret" the rules to some advantage but continually probe areas that yield an on-track power benefit.

From a practical standpoint, this quest for an edge leads to finding ways of evaluating changes that may either point toward or quantify the gain. Air flow benches, engine dynamometers, PC-based software packages, and other means of evaluation are frequently the yardsticks-the results from which are typically enhanced by operator skills and experience. And, quite frankly, the level of intellect now woven into the fabric of circle track engine development includes participants of the highest academic levels, populating the established network of builders who've accumulated decades of well-earned knowledge in the hard-knocks trenches of racing.

So what's the point of all this rhetoric? Changes in the way an engine's combustion efficiency is measured are emerging at the "grassroots" level, if you'll allow me the use of that term. On a week-to-week and season-to-season basis, these are the people who provide the experience while advancing the sport and business of circle track racing. Well, there's a new tool they may soon be using and, believe it or not, it's emerging from the environmental community where an engine's exhaust emissions are of concern and measured.

In the course of sharing this monthly column with you, we've advanced several ways to utilize a variety of engine conditions and measurables. Understanding engine cycle analysis (real-time cylinder pressure vs. crank angle data), reducing brake-specific fuel consumption (b.s.f.c.) into its elements for evaluating combustion efficiency, ways to quantify airflow pressure distribution maps in an induction system, and some of the basics of intake and exhaust parts selection and matching have been discussed. What he haven't chosen to do is introduce ways that evaluate combustion byproducts, as they pertain to how efficiently an engine is converting fuel into heat (power) . . . until now. It turns out this may be a new frontier by which racing engines are placed alongside their production, on-highway counterparts to determine not only emissions output but (coincidentally) become built to even higher levels of power and efficiency.