Gasoline Direct Injection

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GDI (Gasoline Direct Injection) was introduced as early as 2000. It now may become more important with cars that are powered with E85. Shown above is an Opel GT with a turbocharged 2.0L engine that uses GDI to develop 260hp. Green Car Congress relays an announcement from Robert Bosch Corporation and Ricardo plc. They are jointly developing an advanced turbo-charged, direct injection gasoline engine system that will offer superior performance and fuel economy, while achieving SULEV (Super Ultra Low Emission Vehicle) standards.
DI BOOST is the name being given to the prototype system. The GCC article suggests that Bosch will use their recently developed piezo injector for the gasoline direct injection, which was first introduced on the Mercedes-Benz CLS 350 CGI.
Rafael Seidl comments that “BMW, VW / Audi and Mercedes all have turbocharged GDI engines on the market. Even Opel, GM’s German subsidiary, has a good 2.2L turbocharged GDI design.” Patrick then observes that “Mitsubishi beat everyone to market with a turbo GDI engine in 2000. 4G93T 1.8L DOHC, GDI, Turbo, 10.5:1 static CR and 165hp.”
Sid Hoffman reminded the other commentators that General Motors already sells the turbocharged direct injection engine in the United States; and, Seidl carps that the Pontiac Solstice and Saturn Sky are both re-badged Opel GTs (260hp out of 2.0L).
As previously mentioned, the two liter turbocharged Ecotec engine generates 260 hp and 260 lb.-ft. (353 Nm) of torque. The high performance engine features gasoline direct injection and variable valve timing. Its twin-scroll turbocharger also has an air-to-air intercooling system.
Seidl got to a key issue debated previously. Instead of putting efficiency gains into downsizing and fuel economy, they put them into yet more useless power.
Turbocharging and GDI plus cam phaser are a great combination, but you only save fuel with it if you bring the displacement down and apply some long gearing in the tranny. That’s why applying this to a 3.6L V6 is fairly ridiculous, unless you’re still looking for ultimate performance and prices at the pump etc. be damned.
Andrey agreed, “I would rather see further development of Daewoo transversely mounted inline 6, developed with participation of Porsche and inherited by GM when they bought Daewoo.”

A Saab concept 9-3 convertible at 2006 British Motor Show. If a plug-in, flex-fuel hybrid this would be exactly what Plug-in Partners says is ideal for the near future.
Other GM development has been in the area of flex-fuel vehicles. GCC also ran a recent story about the Saab BioPower Hybrid shown this past week at the British International Motor Show and previously shown at Stockholm Motor Show.
The prototype uses a Spark Ignited Direct Injection system. One advantage to such a direct injection system is that it can provide optimum combustion with ethanol blended gasoline. Developers claim that the prototype, even with E100 demonstrates “the same cold-starting performance as a gasoline engine. Variable inlet and exhaust cam phasing is used for optimum air flow and more durable valves and valve seats are fitted, together with bioethanol-compatible materials for the fuel system.”
Ethanol increases fuel octane and reduces temperature, thus reducing knock, which then allows for increased manifold pressure and an increase in compression ratio. As previously noted, the high octane rating allows the engine to use massive levels of turbo boost without the need for lowering the engine’s compression to reduce knock.
A split-parallel hybrid with a 2.0-liter E85 flex-fuel engine (a Saab BioPower engine) and a 67 kW motor with a 288V NiMH battery pack in a stock 2005 Chevy Equinox was the Virginia Tech team entry that took top honors today in the Year Two Challenge X competition. Nevertheless, it still is a far cry from a Compound Turbine / HCCI genset in a serial hybrid.
While General Motors is working on HCCI, the idea of a compound turbine comes from NASA and this blog suggested Compound Turbine / HCCI serial hybrid. It would be a plug-in hybrid with advanced power management of 1) storage and utilization of electricity from the Grid plus 2) what comes from the two or more generators.
The small compound, internal combustion engine drives one generator. The big electric motor that propels the vehicle, of course, also serves as a generator. The motor becomes a generator during (regenerative) braking. In an advanced design other generators would be distributed throughout the vehicle, to include linear actuators that provide (regenerative) suspension.
Lastly, as this blog previously suggested, all power from the generators could go into a bank of ultra capacitors. Advanced power management is necessary to balance 1) the energy stored and quickly available from the capacitors with 2) a large quantity of energy obtained from the grid and stored in the vehicle. Most likely such storage would be polymer lithium ion batteries. They would provide sufficient energy for a suitable number of all-electric miles.
A later recursion…
In the commentary, Bob was worried that he had clicked on something other than the Green Car Congress link. What the heck has proposing a huge gas guzzler got to do with promoting green cars, he asks? And, I advise him to imagine that they are discussing more efficient generator sets in a plug-in hybrid. In other words, if sticking with spark ignition, then direct injection is an improved way to handle ethanol blends up to E100. To this blog’s thinking, the commentary was indicative that when plug-in, flex-fuel hybrid cars are widely available, there will be much greater emphasis on choosing the most fuel efficient, least expensive, cleanest genset.
 

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