Courtesy of Engine Builder
When you work as an auto technician, high performance is rarely a topic in your normal day-to-day routine. The majority of the motoring public bringing you their car simply doesn’t care or know about the nuances of an engine. They only want their car to start and run with no warning lights, no weird noises, cold air conditioning, and a good radio. If you can make all that work, you’re going to make most of your customers happy.
The interesting aspect of modern vehicle technology is that much of it, as it relates to performance, is a result of lessons learned from racing. In the context of engine performance, the same is true, and though most vehicle owners don’t care, as technicians we can easily draw parallels between an everyday driver and the high-performance characteristics that are associated with their engines.
One of the primary factors is engine timing. As engine builders know, degreeing a cam is critical for a high-performance build. If you skip the step, aside from the potential of engine damage, there’s a very likely potential for power loss, and while it might be comparatively minor, it’s just not acceptable. As technicians, this isn’t something we do as part of a standard repair, because again, our customer doesn’t care. If you’re replacing a worn-out timing chain or camshaft, your customer will be tickled pink that their engine runs good again, and timing only involves lining up the marks and moving on.
Years ago, nothing about the stock engine was that precise anyhow. But that was back then. Today’s world is different. Anything less than perfect timing has never been acceptable in the performance world, and now, it’s not acceptable by auto manufacturers either. The critical importance of valve timing is not lost to them, and variable valve timing coupled with computer-controlled technology means today’s engines, regardless of where they rank in the performance world, rely on perfect timing for drivability, performance and economy.
Engine timing has become so critical for overall performance, that not only does the computer store a trouble code with even the slightest of deviance from programmed parameters, but determining a timing issue has become one of the more recent diagnostic topics, and the use of cylinder pressure transducers coupled with an oscilloscope allows us to interpret cylinder pressure, and by comparison as well as learned knowledge, we can determine without teardown if there is a timing-related issue.
When it comes to engine repair, as auto technicians, in many ways we have it easy because we don’t have to make decisions on what to use and how to install it. We use the correct replacement parts and follow instructions. Of course, we still just line up the marks. As long as we get that correct, the computer will do the rest. But building an engine is a different story, and timing components take no less consideration than any other component. Performance engine builders have to make the choice and have to set it up right. Their reputation is on the line, and the choice comes down to chains, gears, or belts – each one with distinct differences and pros and cons.