From HJ's breakdown:
"The engine that Volvo Cars has chosen for the Volvo S60 Concept is a four-cylinder 1.6-litre petrol unit using high-efficiency GTDi (Gasoline Turbocharged Direct Injection) technology and producing 180 horsepower. In a conventional petrol engine, fuel is injected into the inlet manifold ahead of the inlet valves. With direct injection, however, the fuel is injected directly into the combustion chamber under high pressure. The engine in combination with a range of other technical measures makes it possible to cut carbon dioxide emissions to 119g/km."
Is Volvo serious about introducing this engine into the production version? Those figures are incredible, and must give diesel buyers something to think about, given that 119g/km has to be accompanied by mpg figures somewhere up towards the 50's, and on fuel that's still about 12p per litre cheaper. I have the prececessor to this car with an engine making the same power output but from 400cc more and with 100g of extra CO2 per km. To me, this is real progress in terms of raw figures, although I would miss the five pot burble.
The other thing that strikes me is that direct injection petrol engines such as the VW FSI and Ford SCi (and probably others) have a pretty poor reputation for reliability and engine longevity, so has Volvo done something different? It's strange to think that the manufacturer with probably the greatest reputation for product longevity and long term reliability in the industry would showcase a technology that is inherently flawed. Or has the green argument won over common sense (as with DPF)?
Thoughts?
Cheers
DP
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The key word here is "Concept"
If you think a 1.6 litre turbo charged engine is going to give you an average of +50mpg in day to day proper use then you also think you will get the
"a floating centre stack made of hand-crafted Orrefors crystal. It is shaped in a graceful, transparent wave from the instrument panel all the way to the rear seat backrest. The crystal panel appears to float above the centre stack's ergonomically designed functionality and it rests gently on rubber pads."
On second thoughts you wont get that either.
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Hence my comment that the figures were "incredible". That said, if they are claiming 119g/km, that must be verifiable in some way. If it genuinely emits 119 g/km, it *must* do 50 mpg.
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How is the 119g/km CO2 emissions figure arrived at? I bet it's not when the thing's producing 180HP!
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The first modern DI petrol was the Mitsubishi and was not known for it's durability tho' it was claimed that it was developed on Japanese lead free fuel and not EU unleaded.And before someone asks-Unleaded has had no lead added(but contains as tiny % of naturally occuring lead).Lead free has had ALL lead chemically removed.
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Notice how fast Citroen dropped the HPi engine.
Still would be nice if they could make it work.
Steve.
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Notice how fast Citroen dropped the HPi engine.
I had that engine a company Peugeot. For the second 18mths of its time with me the engine management light was on and it misfired the whole time. It spend weeks at a time in the dealership.
We had 2 on our fleet and Peugeot took the other one back early and then the leasing company asked me to return mine at 60K as Peugeot wouldn't do any warranty repairs beyond 60K.
Some poor devil probably bought it at auction thinking it was a lovely looking car.
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119 g/km in a petrol engined car makes it more like 56mpg. Add in the cheaper fuel it's like getting 60mpg in a diesel, cost wise. That is remarkable for a 1.6L petrol. If it can really do 180bhp at the same time I think I'll be able to live with a 4 pot whine!
Is it possible? I guess so, in that manufacturers have only recently been taking the issue of emissions truly seriously. In fact, given time and greater developments I'd hope for even better.
This is great news with our governments trying to get average emissions down and down, who knows we might still have cars we can enjoy driving despite brow beating from the green lobby and greedy tax collectors. trying to empty our pockets.
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The problem with engines like this is that however good an idea they sound, they usually seem to involve a big dose of added complexity, which increases maintenance costs and shortens the vehicle life.
I think that the quest for ever-more efficient engines is a dead-end path of baroque technologies. Rather than adding ever-more gadgetry to wring the last drop of efficiency out internal combustion engines, it would be much better to set about removing weight from cars. It's daft that a Focus-sized vehicle now weighs about 1.35 tonnes; it should be possible to make them at half that weight by using composites.
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Sure, you can make them much lighter, but a whole lot less safer too.
Manufacturers haven't added all this weight for nothing, it's all our airbags, side impact bars, whiplash protection systems etc, etc.
For me, I'd rather have a car equipped with all this stuff and a nice complicated engine to help compensate. It's not like the simple engines of old were all that wonderful, I remember too well my old Orion 1.6. It could barely do 30mpg and the oil sludging was terrible. It was very light, but I wouldn't fancy crashing in one. So what was so great about all that?
Fancy engines and heavy safety systems are generally called progress and I like to think it's a good thing. ;)
One day the internal combustion engine will be obsolete, but we're a very long way away from that reality. In the meantime, bring on the complexity. As long it's well engineered and tested I don't see a problem.
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"it should be possible to make them at half that weight by using composites."
I think if you used the right materials you could make cars lighters, stronger and safer. But will anyone be able to afford to buy one. A Focus would not be nearly as cheap.
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"it should be possible to make them at half that weight by using composites." I think if you used the right materials you could make cars lighters stronger and safer. But will anyone be able to afford to buy one. A Focus would not be nearly as cheap.
Yup - an F1 monocoque tub is very very strong and very very light. You cant afford it tho.
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AE - when I said "not nearly as cheap" that was meant to be sarcasm or similar. It would cost a fortune to make cars both safer and lighter ;-)
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Is that really true? I know the setup costs would be huge, but carbon compsites and so on seem fairly suited to mass production to me. They could be blow-moulded into forms, and the energy costs are not that hideous, certainly not when their competitor is heating steel to well over 1000 degrees.
Yes, the setup costs could be pretty steep to say the least, but I think volume could do a lot to attenuate that barrier. Maybe?
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>>but carbon compsites and so on seem fairly suited to mass production to me.
It's a cottage industry at best, it is extremely labour intensive and has long cycle times. This is why serious structural uses of carbon fibre are limited to small production runs, like satellites, large civil airliner parts, F1 cars, competition boats / parts, etc, etc.
I'm currently having some CFRP parts made for a project I'm working on. I hate the stuff, because it's structurally quite difficult to predict how it will respond to temperature changes. It also has a co-efficient of moisture expansion, which is something you don't need to worry about with proper materials.
There's a fairly old OU book on "The Car Body". While it is out of date in that both materials and their processing technologies have moved on a bit, it's analysis of appropriate materials for vehicle structures in low, medium, and high volumes is still relevant. Well worth a read if your library has a copy. For Marina enthusiasts, there's also a discussion of the EN8 steel used to form the lower suspension arm - something for everyone!
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What I've seen of CFC parts, is that it takes a lot of time and care. Layers to be placed in a given sequence, clean room, bonding in metal parts and attachment points, vacuum forming, curing, autoclaving. Expensive.
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Layers to be placed in a given sequence, clean room, bonding in metal parts and attachment points, vacuum forming, curing, autoclaving.
Yes, that's the drill.
I'm backed into a corner, and don't have much option on my current project but to use it. Otherwise, it's right at the bottom of the list of materials that I would consider.
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Id much prefer they persue the lightweight direction as it has alot of room to make gains without creating mechaincal complexity.
The weight of just a doorcard on your average family car is something to experience. Lots of little gains in non-structural places is no bad thing and Im sure that a wholesale lightening process on some family cars would be quite possible.
Less is more.
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>>Boeing?
No. I did some CFRP work on the A380 (for the company where the BR member cub leader did a sandwich year), but I'm currently working on a research project to demonstrate alternative low expansion structural materials for spaceborne precision measurements.
The materials used in these applications at the moment are glass or glass ceramics like ULE or Zerodur. These have nice low co-efficients of thermal expansion, but are susceptible to brittle fracture - not ideal for surviving launch and seperation shocks.
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Ah! Impressed. Ceramics. Rather like Corsa camshafts. Light, even hollow, but not very robust:)
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