Intake manifold construction, intercoolers

[Bernd Felsche]

Greg Hermann tapped away at the keyboard with:

> >> You are wrong, in part, Moe. Multi valve on street engines came
> >> from EPA (and CAFE) rules, every bit as much as EFI and ALSO SOHC
> >> and DOHC has.

> >> Multi valves make higher valve velocities possible--which allows
> >> reasonable lift values with short duration--directly related to
> >> both emissions and CAFE-- and SOHC and DOHC not only tend to allow
> >> higher valve velocities, but also facilitate variable valve
> >> timing--which are also emissions and CAFE induced features as far
> >> as street motors are concerned .

> >Which must come as a hell of a shock to the likes of Alfa Romeo,
> >Porsche, Jaguar, Mercedes, etc. who used those particular bits of
> >technology to gain a competitive edge (in more ways than one) and
> >to set themselves apart from the crowd.

> >Engineers tend to like to make something better than what already
> >exists. Well, Engineers worth their salt.

> Perhaps I should have said "mass market" cars, rather than "street" cars.

What's a "mass market" car? One that appeals to the great unwashed?
You expect leading-edge technology in motorised shopping trolleys?
The only "hi-tech" that appeals to the "masses" is cup holders and
CD stackers. They don't have a clue what the "DOHC", "16V", "PORT
INJECTED" and "TORQUE CONTROLLED" decals mean; nor do they care.

BTW: I've seen those decals and their ilk on motorised shopping
trolley for the past 5 to 10 years.

Don't mix "mass market" and competition paradigms. They are at
opposite ends of the scale. Take your average "mass market" car
around a race or autocross circuit to anywhere near its limit and
you'll find that it will expire very rapidly, if you don't lose
tyres or off the car first.

EFI is appealing in mass market because it is CHEAP to build,
install and maintain (over the nominal life of the car). That
appeals to mass-market _buyers_. The number of new cars produced
with carb'd engines is very small - production is restricted to
developing countries. TBI is the LCD, and is diminishing as _buyers_
migrate to engines with port-injection due to better drivability and
fuel economy.

It'll take another 5 to 10 years before direct gasoline injection to
reach the market penetration of port-injection. Partly because of
fleet ageing, partly because of the cost reductions that come with
development.

The mass-market motivators for trickling down the technology are
fuel economy and driveability. Performance helps, but is more a
function of the total car package, which has become heavier due to
legislated requirements, despite engineering efforts to minimise
vehicle mass.

> Not to mention that competent engineer/tuners are quite capable of
> making Weber DCOE/IDA carbys perform at least as well as EFI !

Under all nominal operating conditions? On all sorts of cars?
At a price the customer can afford? I very much doubt that.

> Also, not to mention that Jag's competitive advantage came
> virtually entirely from being the first to adopt the use of disc
> brakes in competition!

So their chassis design was of no tangible benefit?

> Greg (raced an Alfa Guilia Spider Abnormale and tuned a GTZ for
> years, both of which were very quick indeed (especially the TZ),
> but both of which also lost REGULARLY to pushrod motored Cobras---
> although NOT to Porsh*ts) (Also once had a pal who was a member of
> Ecurie Ecosse, if you want to argue the particulars of Jags !)

There's an Alfa locally that's unbeatable in the Sporting Car Club.
It's only the when megabucks arrive that even have a chance of
showing it up.
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