Intake manifold construction, intercoolers

[Bernd Felsche]

Bruce tapped away at the keyboard with:
> From: "Bernd Felsche" <bernie at innovative.iinet.net.au>
> > Bruce tapped away at the keyboard with:
> > > Higher rpm, OK, how high are you talking about.  The thread
> > > started with street cars, are you still working the street or
> > > moving into the race field I'd hardly call 250d at .050 as a
> > > street engine.

> > Depends on number of cylinders and method of induction.
> > My 4-cylinder car's NA with 270 degrees and more than 10mm lift.
> > It's only a bit lumpy at idle.
> 
> 270d @ .050 clearance?
> 270 @ .005 maybe.

@1 mm -- It's a Kent GS2H and used most days in traffic.

Serious competition "Golfers" run asymetric cams with longer
durations; 300 degrees or more. (Ref Greg Raven's book on the
subject)

[snip]
> > If you want to see how much of that technology is filtering down
> > into production cars, I suggest you browse through SAE's Automotive
> > Engineering magazine occasionally.
> 
> > Cars built on space-frame: yes - FIAT and Audi
> > Multi-valve engines with variable manifolds: yes - most manufacturers
> > Dierect gasoline injection: yes - Toyota, VW-Audi, Mitsubishi
> > Turbo-multivalve engines: yes - Volvo, VW-Audi, Subaru, etc.
> > Independent cylinder throttling: yes - BMW (3 series and 7-series)
> 
> We were talking engine technology.
> F1 didn't discover multi valves.
> Direct injection has been used for years in IH tractors, and the
> 300SL did also.

Vastly-different DI in the 300SL. It wasn't stratified-charge for
one thing. And purely mechanical. By your definition, it wasn't a
street car anyway. :-)

> 2 models of one manufacurer, OK, but big deal

Much more than two models. VW-Audi technology is shared throughout
the Volkswagen Group across 8 marques and over 50 models. There'll
be at least 6 distinct VW-Audi models with stratified-charge DI on
sale from early 2002. There are at present two (VW Lupo and VW
Golf), with the Audi A4 2-litre FSI on sale before the end of this
year.

FSI engines operate unthrottled in stratified-charge mode, greatly
improving efficiency.

Not pipe dreams. Not theory. Real, volume production cars on the
road.

It's only "one" manufacturer. BMW will have Valvetronic engines
available for their whole model lineup next year. Their larger
engines already have DI available; at least in Europe.

Why is this only happening in Europe?

The answer is sulphur. The VDA (German Association of Automobile
Manufacturers) lobbied the oil companies to produce "sulphur-free"
gasoline. Without that fuel, you can't operate in lean-burn mode
very long as NOx emissions would be excessive and a storage cat to
handle them becomes contaminated very quickly.

BTW: The Veyron was recently shown in Frankfurt. Here's a snipping
from the press release:

  Tu 2001/09/11

  Development progress: the Bugatti EB 16·4 Veyron in the autumn of 2001

  Molsheim, September 2001. At the 59th International Automobile
  Exhibition ('IAA') Frankfurt, Germany, BUGATTI Automobiles S.A.S.
  are displaying the 736 kW (1001 bhp) Bugatti EB 16·4 Veyron in its
  latest evolutionary stage. Both the power train and the body of the
  new design study are much closer to production maturity. In
  addition, the first theoretical performance figures have now been
  determined, according to which this 16-cylinder sports car, due to
  go on sale in 2003, will have a top speed of 406 kilometres per hour
  and accelerate to 300 km/h in under 14 seconds.

  ...

  New technical elements in the W16 engine

  The alloy-block W16 engine in the Bugatti EB 16·4 Veyron is
  innovative and totally unique. Two exceptionally narrow V8 cylinder
  blocks using the VR principle are combined at an included angle of
  90 degrees. The resulting 16-cylinder engine can develop a mighty
  736 kilowatts (1,001 brake horsepower) at 6,000 revolutions per
  minute. The W16 is installed as a mid-engine ahead of the rear axle,
  and measures only 710 millimetres in length and 767 millimetres in
  width.

  Its W pattern is not only the key to these compact dimensions and
  the generous engine size and power output from such a compact unit;
  it also makes the engine exceptionally rigid.

  Four turbochargers help to give this 7,993-cc engine a peak torque
  never before available in a passenger car: 1,250 newton-metres. The
  temperature of the charge air is reduced by passing it through two
  water-cooled charge-air intercoolers located above the cylinder
  heads. No fewer than 64 valves admit the mixture to the cylinders
  and expel the exhaust gas; they are operated by roller cam followers
  from four chain- driven overhead camshafts with continuously
  variable valve timing.

  The continuously variable electro-hydraulic camshaft control system
  is active in all operating conditions. ...

  ...

  7-speed gearbox

  Had it not been developed specifically for the Bugatti EB 16·4
  Veyron, the new seven-speed gearbox could well have come directly
  from the pen of a top Formula One racing car designer. Gear shifts
  take place sequentially at paddles behind the steering wheel, and
  there is no clutch pedal. The double clutch transmission (DCT)
  shifts from one gear to the next in a maximum of 0.2 of a second.
  Power from the engine reaches the wheels through a permanent
  all-wheel drive system.

Figures are a little different to the previous ones due to design
revisions.
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