when Detroit began offering roller cams with more aggressive profiles |
Posted: August 24, 2018 |
There was a TDC corner quantum leap in the ’80s when Detroit began offering roller cams with more aggressive profiles, better cylinder heads and induction, and finally electronic fuel injection. Performance only got better in the years to follow thanks to the extensive effort of Motown’s best engineers and product planners. Variable valve timing and intake runners got us more power and a broader torque curve. These days, Detroit has moved toward direct injection in its quest for even better fuel economy, reduced emissions, and vast amounts of power. There are no free lunches when it comes to getting performance. Making power is like making money. Were it easy, everyone would be doing it. It takes a lot of effort to gain modest amounts of power because it’s all about heat energy and how we turn it into power at the crankshaft. The challenge with heat energy is harnessing as much of it as possible to turn it into power at the rear wheels. And by the way—there’s more to channeling power than just the engine. Electronic engine control has evolved into powertrain management where automatic transmissions have become an integral part of engine management where the two work together for better overall performance. We see this most from having a greater number of speeds in automatic transmissions, which keeps engine rpm more constant as we navigate the cogs. Did you know just 25 percent of the heat energy generated in the combustion chamber is used to actually make power? That means 75 percent of the heat energy created by the light-off above the piston is lost to the atmosphere. A full 50 percent of it is lost out the tailpipe. Another 25 percent is lost to the cooling system. Making power is straight physics. We’re taking intense fury of fire—thermal expansion—and acting on the pistons, connecting rods, and crankshaft to turn linear action into a rotary motion at the flywheel or flexplate. When you observe how engine power has evolved over the past century, it is remarkable how far we’ve come even in the past 50 years. We have a better understanding about how power is made than we did a half-century ago. Computer analysis along with pressure from Washington and the buying public has gotten us more powerful, fuel efficient, cleaner-burning engines.
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