I've just come back from a day in Milan where I was taken for a spin in a 4WD Passat W8. The engine sound was fabulous and the acceleration was quite something.
After a bit of Googling I found a diagram of the engine layout ( tinyurl.com/9hnen ) which put the questions I had to bed. I previously thought that a W(2x) engine was two V(x) engines stuck together in a W format - doh!.
What a Q car though. Whip the W8 badges off and there's fun a-plenty to be had I'm sure. Are there any in the UK? I've not heard of or seen one clearly. I was told that the W8 I went in was one of only two in Italy but I'm prepared to be advised otherwise!
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It may be one of only 2 in Italy but there are 5 on AutoTrader, all 2002 models, priced from £10,750 - £14,995.
VW is now selling the Passat in the USA with an even more powerful 3.6 litre V6 and 4 wheel drive for rather less than the cost of the W8 - which could be even more of a Q car. Fuel economy is also surprisingly good. Not sure if and when Europe will be getting that engine though.
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they are/were sold here but the cost !!!
very expensive / high depreciation
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That W8 engine has been dropped. Once upon a time in a "Motor" magazine that BigBadDave works in, it just came on fire during a test drive.
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I am the only Pole over here.
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Not my fault I might add, I?m not allowed to carry matches anymore as part of my treatment.
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Anymore ... ?
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I am the only Pole over here.
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I have only seen 2 W8s on the road; the badges are very inconspicuous. There were quite a few available second hand in VW dealers a couple of years ago. The W8/W12 etc layout is understandable once you realise that the VR6 is a very narrow angle V, more like a staggered inline engine (has a single engine head), hence making vee engines from 2 of (variants of ) these blocks forms a "W"...
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Which taked us back to the Bugatti Veyron again - it's a W16 - two narrow angle V8 (or could be described as staggered straight 8) blocks mounted on in a V on in the same fashion as W8 / W12 engines.
Cheers SS
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How does the angle of the "v" change the characteristics of the engine? What's the big difference between v and straight?
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BBD,
Heretic as I am, I think there isn't anything at all special about v engines.
Where you have the availability of both types, say 4 or six cylinder engines, there isn't much to choose. The v engines are easier to package, but not intrinsically better in any way.
When you go beyond six cylinders, the crank in an inline engine begins to become too long. The torsional stresses become too great, and crankshaft life becomes a problem*. A v engine allows a larger number of cylinders within a given crankshaft length. A v or horizontally opposed engine is really the only viable solution for large numbers of cylinders.
Some people get all excited about v8s and v12s, and the equivalent horizontally opposed engines, but there really aren't any (modern) comparable inline engines. Who knows how good a straight 12 sounds?
Number_Cruncher
* to be pedantic, the fundamental natural frequency of the crankshaft, in torsion, for a long inline engine is too low, and can be excited by the firing impulses.
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"there really aren't any (modern) comparable inline engines"
Hence the excitement.
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V6 = less vibrations
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I am the only Pole over here.
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V6 = less vibrations - - - - - - -
Less vibration compared to what?
Number_Cruncher
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The reason I ask is that a straight six is among the smoothest of engines, as summarised below;
Primary imbalance force - none
Secondary imbalance force - none
Primary imbalance moment - none
Secondary imbalance moment - none
A straight six doesn't need added balancer shafts to correct these imbalances. V6 engines tend not to be free of these fundamental types of vibration, typically there is at least an unbalanced pitching moment. Some manufacturers fit a balancer shaft, and blow their trumpets because of it, but a balancer shaft is a heavy and clumsy way to reduce these vibrations.
Sometimes as well as compromising the balancing, the firing interval is also upset on v engines. Yuck!
Number_Cruncher
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>> V6 = less vibrations >> - - - - - - - Less vibration compared to what? Number_Cruncher
Compared to a simple R4 engine.
I'm just amazed when I look at your statement:
"...Where you have the availability of both types, say 4 or six cylinder engines, there isn't much to choose. The v engines are easier to package, but not intrinsically better in any way..."
V engines not better in any way ... ? No way !
Take a ride in a 1.6 R4 current-shape Corolla or even Avensis 1.8/2.0 R4 and then try Camry 3.0 V6 - you'll see what I mean.
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I am the only Pole over here.
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What I'm getting at is that there is nothing 'special' about the v configuration.
Taking engines of comparable size and type (i.e. not comparing a truck engine with motorbike engine), If you compare a straight four with a v four, or compare a straight six with a v6, the v engine doesn't confer anything other than a packaging advantage for certain types of vehicle.
This is why I say that a v is not intrinsically beter in any way.
Number_Cruncher
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The narrow V has been used many times, although I don't recall any other W or compund V engines. To me, it's a cramped messy design, with complex valve / port arrangements.
Th narrow V creates a 'fatblock' and inlet / exhaust valves cannot be handled by a conventional DOHC arrangement - a minimum of triple cams or rocker arms are required.
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