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somebody on nabisco posted this. Pretty interesting stuff

http://world.honda.com/HDTV/news/2003-4031127a/

So that everybody not familiar with Metric ratings can gauge this engine's performance:

HP: 154.1@6300RPM
Torque: 138.66ft-lb@4600RPM
Fuel Economy: 35.28MPG (in test minivan in 10-15 mode)

That's really crazy. The thing has respectable horsepower for a 2L engine, and has fine fuel economy under all driving situations. Jeez.

See Honda. See Honda come out with new engine tech. Yeah Honda. See Subaru. See Subaru design own version of engine tech. Yeah Subaru.

What I'm waiting for is Subaru to get that twin-clutch semi-auto transmission that Audi's selling to the rest of the world. Sounds a hell of a lot better than the auto I've got now.

That's pretty awesome man, That video has some crazy graphics too

It's kinda lame that it's being put to use in a minivan, but hey, what can ya do?

-James

Basically it seems like an update for their old stratified charge injection CVCC technology. The problem with SCI is high NOx emissions. Not sure how this has been overcome as I don't get sound (if they explain it), though I'd guess it would have something to do with the converter.

Steve

I've got sound. They made some kind of advancement with the catalytic converter. There's a part of the video near the end in the "Low Emissions" section that shows a bunch of yellow particles getting caught in a red catalytic converter.

So apparently they realize the problem and have solved it, considering the rating that the Japanese gave it. Ultra-low Emissions, I think it was? I don't feel like watching the vid over again... stupid non-functional scroll bar.

That's what I figured as it's one of the main things cats clean up. Excellent. I can't wait for direct injection to be as prevalent as MPI. A lot of 2-stroke outboards have it and they get decent emissions (for a 2-stroke). Fuel's so much more controllable and here you can actually get SCI to work in today's strictly regulated environment. Unfortunately, they'll probably negate possible fuel savings by making more power instead (to offset massive weight gains?) as they've been doing with most engine tech.

Steve

The 05 VW Jetta has direct injection. What are the advantages of this?

The first ever privately owned 05 Jetta is owned by a friend of my neighbor at the University of Maryland. The 2.0L base 4cyl makes the same power as the old 1.8T.

We use direct injection on our large two stroke industrial natural gas engines. HPFI technology is being upgraded on these engines to help improve mixing and control of the engines. NOx is one of the major concerns. In our case, the best we can get with NOx is where CO & NOx curves intersect. If that's not good enough, gotta put a catalyst on.

Yeah, direct injection SI engines are way cool. Audi's got some production gasoline direct-injection engines that they first started selling a few years ago. Mitsubishi was one of the first to actively research it, and they developed the engine Volvo's using in some of their cars.

And BMW's new 7-series has a GDI motor option, too. It also has extremely flexible cam timing and lift control, so it doesn't even need a throttle plate. They're working on making it camless, too.

It looks like Honda's applied their magic touch of efficiency to the new technology, though. That's really cool how they use the valves to control the airflow pattern instead of requiring the fuel to be injected at an angle and having an asymmetrically funny-shaped piston.

Those CG animations are way cool too.

I wish they'd go to rotary valves driven by servo motors. I could go on for pages about the possibilities there for timing, duration, opening shape, etc. plus there's the less parasitic drag. Ally that with direct injection and displacement on demand or a turbo and that would be amazing. Power, emissions, etc. Even serviceability may not be bad depending on how the injectors were put in the heads, but better packaging with the rotary valves would make a big difference. This would also allow lower hood lines on inlines and increased stroke on boxers due to less space required for the valvetrain ... Oh, shit I'm going on about it. Anyway ...

The 05 VW 2.0 makes the same as the 1.8T ... well not being the 1.8T makes it a huge improvement to begine with! Wonder if they fixed that horrible oil pick up design.

Steve

The engine also uses a "precision" EGR valve system to inject a lot of EG during high load situations to keep the cylinder temps down.

Yeah. From what I understand, precision EGR like that is a lot like water injection, especially if it includes an EGR cooler.

Didn't the CVCC do that, but use valve timing to burn exhaust gas? I might be remembering that wrong, but that would be damn cool if they updated almost 30 yr old technology (advanced for the time) to work today more efficiently. I respect that kind of allegiance to an idea.

Now rotary valve triple-expansion steam engines ...

Steve

I don't really know anything about CVCC except that its control system was essentially a pneumatic computer and a nightmare to diagnose and repair.