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October 23, 2009
Engine Parts
What’s Next?
People in the automotive aftermarket who don’t like change must be very frustrated today. But, as they say…you ain’t seen nothin’ yet! The future in automotives is coming fast—so as a successful service provider, you need to be ready for it.
Who would have thought plastics would be underhood! Plastic engine parts are here—one of Ford’s 8-cylinder engines has a plastic valve cover— it sits on top of the engine and keeps oil circulating. Both GM and Chrysler are fabricating limited amounts of plastic engine parts. Why are they doing this? Weight reduction, plus plastic parts cost less than many metal parts. After it has been molded, plastic has a smooth finish, thereby requiring little, if any, machining— less work goes into the parts making it cheaper to create. And speaking of less weight, aluminum is now being used for side housing in some vehicles i.e. Mazda. In the 2.0L diesel engine, they’re using an aluminum block and have thoroughly reduced the size and weight of reciprocating and rotating parts.
Direct-Injection
Soon you’ll be dealing with new engines from various automakers—some with gasoline direct-injection fuel-saving technology. As well as saving fuel, some engines will be able to deliver increased horsepower. Direct-injection is a method of cooling of the intake air temperature that plays a role in improved power output by increasing air mass. It’s also a good way to get the better of abnormal combustion i.e. engine knock or pre-ignition which are usually caused by the higher compression ratio. The system injects gasoline in a high-pressure spray during the intake cycle and so forms a stable air-fuel mixture. You can find out more about direct-injection from the office of Energy Efficiency, Natural Resources Canada (www.oee.nrcan.gc.ca/english/ programs/pdfs/Doc3e.pdf).
Here’s what they say: “GDI is attractive to 2-stroke engine designers because of the inherent ability of in-cylinder injection to eliminate the exhaust of uncombusted fuel during the period of overlap in intake and exhaust valve opening. In principle, GDI technology’s inherent efficiency advantages make it attractive to both 2- and 4-stroke engine designers. While the greatest fuel efficiency advantages of direct gasoline injection can be realized in direct-injection stratified charge (DISC) lean combustion applications, significant fuel savings can be achieved even under stoichiometric operation. As in current production engines, the theoretical fuel efficiency gains of GDI technology must be balanced against its emissions performance.
“GDI controls engine load through the volume of fuel injected into the cylinder and requires no air throttling, resulting in significant thermodynamic efficiency improvements through excess air combustion and the elimination of throttling losses. In an optimum configuration, the efficiency of a GDI engine approaches that of a diesel direct-injection engine both in fuel consumption (when corrected for density differences between gasoline/diesel) and carbon dioxide emissions. Although the GDI concept is not new, the complex fuel injection and charge control technology required to make it a production reality has only recently been developed. Sophisticated high-pressure injectors capable of producing very fine, well-defined fuel sprays, coupled with advanced charge air control techniques, now make stable GDI combustion feasible. Emissions constraints, however, must be addressed before GDI can displace current spark ignition engine technology.”
CVT and more
Nissan has improved transmission efficiency and now use CVT (continuously variable transmission), whose technology enables smooth shifting in uneven driving conditions by continuously altering the gear ratio during acceleration/deceleration. This improves fuel economy/driving performance.
Because of the severe exhaust emission regulations coming, Mazda has developed a new catalyst employing single nano technology. This includes a new and original catalyst structure consisting of precious metal embedded in a catalyst support matrix. Because of its key features, the structure ensures that there is virtually no loss of purification efficiency. Another item is the turbo system—a 2-stage turbocharger is used to yield optimally high turbo-pressure over a broader engine rev than previous diesel engines. This is aimed at obtaining a broad, flat curve.
We could go on, but I think you see that the changes coming will require you to get ready for the challenges ahead. You can read about these on various automakers websites or ‘google’ the subject.
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