Paladin06

Camaro may get direct-injection V8
Filed under: Coupes, SUVs, Tech, Chevrolet, GM
The Chevy small block V8 has been around in one form or another longer than many current GM engineers have been alive, but continuous updates continue to keep the venerable powerplant relevant. GM is currently developing the world's first overhead valve Direct Injection engine, giving the 6.2L test engine big gains in horsepower and torque while bumping fuel economy from 3% to 6%.The 6.2L currently pumps out up to 403HP without DI in the Escallade, but Dave Sczomak, development engineer-GM Powertrain Advanced Engineering, says the technology will bump power to "well over 450HP."

Perhaps even more exciting is the possibility that the anxiously awaited Camaro may receive a variant of the engine. The mere thought of the ultra-sexy Camaro packing over 450HP without added boost could make us want to have a smoke. While we're hoping the Camaro gets the DI engine, the halo status of the Corvette makes the two-seater a shoo-in for the improved engine. That would give the base 'Vette nearly 500HP, and it boggles the mind to imagine the output of a Z06/SS/Blue Devil.
Editor's Note: There's no reason to believe GM wouldn't drop the DI V8 in both Corvette and Camaro. Back in December, a source we spoke to who was familiar with Camaro powertrain discussions told us that there was a faction pushing for seriously big power in the Camaro. When we asked exactly how big, the individual smiled and held up five fingers. We'll learn how that pans out in due course. Then in January at NAIAS, Ed Peper specifically told us that there were no concerns with having Camaro step on Corvette, power-wise, as the two cars have such different market positioning -- sports car vs. muscle car. Plus, the ZR1 ensures that there will be a Corvette with power that greatly exceeds that of Camaro anyway. No matter how things play out, there's good reason to expect some real excitement.

[Source: Motive Magazine via GM Inside News]

See pics here.

http://www.autoblog.com/photos/chevy...t/242308/full/

RLSH700

Darn it GM, don't follow my strategy book until I'm finished writing it! Now I'm going to have to rewrite a few things![:@] Chrysler needs to add Direct-Injection to the HEMI as well.

lear4406

I understand throttle body injection. I understand tune port. Multi port injection. Will someone in the know.. please explain the direct- injection and why it performs better, while increasing the mileage. Thanks in advance.

Paladin06

Direct Injection

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Overview

Conventional gasoline engines are designed to use an electronic fuel injection system, replacing the traditional mechanical carburetion system. Multi-point injection (MPI), where the fuel is injected through each intake port, is currently one of the most widely used systems. Although MPI provides a drastic improvement in response and combustion quality, it is still limited due to fuel and air mixing prior to entering the cylinder.

To further increase response time and combustion efficiency, while lowering fuel consumption and increasing output, systems may use direct injection. Gasoline direct injection engines are engineered to inject the gasoline directly into the cylinder in a manner similar to diesel direct injection engines.

Direct injection is designed to allow greater control and precision, resulting in better fuel economy. This is accomplished by enabling combustion of an ultra-lean mixture under many operating conditions. Direct injection is also designed to allow higher compression ratios, delivering higher performance with lower fuel consumption. Currently, direct injection gasoline engines are being deployed throughout Europe in passenger cars.

Key Benefits
Simplifies development procedures for powertrain control system suppliers
Provides additional computing strength for complex applications
Supports vehicle networking with three TouCAN modules
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Design Challenges

Many of the design challenges in a direct injection system involve operation within harsh environments. Designing reliable, cost-effective injectors capable of withstanding the in-cylinder heat has proven to be a complex challenge. Due to the very short time for injection, high-pressure injectors are required. From an electronics standpoint, direct injection engines have a small window for injection. In direct injection engines, injection typically occurs during the intake stroke, allowing only 90° on an eight-cylinder (1.875ms) for total fuel delivery. During higher output modes, fuel can be injected during the intake stroke giving an additional 90° of injection time, a very short time compared to the 720° (15ms) an MPI engine typically has for fuel delivery.



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Solution

Any of the Freescale Semiconductor MPC500 Family members can be used for direct injection. The MPC500 Family of microcontrollers is designed to respond to direct injection implementation challenges based on its operation in a wide temperature range, from approximately -40°C to 125°C, and its high performance. The central processing unit (CPU) runs at speeds of up to 66 MHz. The MPC500 Family supports a wide range of on-board peripherals.

With three timer processor units (TPU3), the MPC565 provides additional computing muscle for complex applications. Each of these units has a 32-bit MicroRISC engine capable of processing up to 28 million instructions per second. Off-chip serial communications are handled by QSMCM modules for universal asynchronous receiver and transmitter (UART) and serial peripheral interface (SPI) functionality. Vehicle networking is supported with three TouCAN (CAN version 2.0B) modules and one J1850 interface. The package option is a 388-pin PBGA.

The MPC565 is the first embedded processor in the automotive market with 1MB of embedded Flash EEPROM memory. It has a comprehensive suite of low-level drivers software, enabling engine control and timing systems. It is designed to simplify development processes for powertrain control system suppliers

lear4406

OK lets see if my thick skull can comprehind. The direct injection injector is mounted on top of the head. Does this mean that the fuel is injected post intake valve. So all the intake valve is doing is pulling in air. The injector is putting the fuel directly in the cylinder and no air /fuel mix passes the intake valve? Does the mixture take place on the intake stroke and compression stroke? And it would seem to me that you would want more mixing time... but test show a power increase and an improvment in fuel mileage. I wonder if the life on the injectors will be less, seeing the increase in heat and oil in that enviroment? Also the injectors themself will be totally different from what we see now, more metal. I can't see any plastic living in that kind of heat stress. I look at valves that come out of an engine with 80000 to 100000 miles and the buildup on the valves is quite substancial. I wonder what the injectors will look like after the same mileage. I'm all about technology and I like it when you get + HP and + gas mileage... I just want to know how it ticks and will it be as dependable as what we have now.

TeeWJay426

Most likely, the long term consequences have yet to be determined, since if I understand Paladin's source, they're just strating to appear in Europe now. Gas engines run at a much hotter temp than diesels, but since most of them are direct injection and have a good track record for longevity, it would seem that the technology should be there to adapt the direct injection to gas engines as well. Be interesting to see what happens.

Axel

I would think that the first year for this engine to be out in the Camaro and/or Corvette, that there are gonig to be problems with it. Anything new out for the first year usualy has some kind of problem and engines are no exception. With that, being that this is a newer technology and Chevy keeps pushing the hp higher and higher then I'm sure that they are going to have to make a decent suspension to back it up. I guess what I'm getting at is, is this Camaro with all this high tech high hp stuff in it going to be the higher end Camaro? I can't see this thing being as cheap as the Mustang with all this high tech stuff in it. Maybe up there with the Shelby Mustang, but definitely not a step up from the V6, more like two steps up. Now if Chrysler would get this way of thinking, Corvette sports car, Camaro muscle car, then we would have one bad Challenger. Unfortunately it's probably more like Viper, top of the line sports car, Challenger, "poor" man's sports car.