I'm referring to both. No argument here, Bernd. The terms have become fuzzy.
I'm not talking exact definitions, but the connotations that people have. I
have heard people use 'ram air' for both. Though usually they say 'ram
induction' when they mean 'tuning' if they don't say 'induction'. As you
point out, there are much better ways to increase psi than 'ram air'. 'Ram'
without any qualifiers refers to tuning and I'll stand by that. People have
been playing with ram tuning since the late 1800s, long before the 100+mph 'ram
air' effects were even dreamed of. I think 'ram air' was a marketroid term
playing off the tuning terminology, though it is a legitimate term for jet
engines and indy cars. Like calling a car a 'Mach I'.
If only things were so simple as two distinct terms.
"Bernd D. Ratsch" wrote:
> And that's the definition that most of the "Ram Air" hoods are using.
> You're referring to Ram Tuning.
>
> - Bernd
>
> -----Original Message-----
> From: owner-dakota-truck@buffnet.net
> [mailto:owner-dakota-truck@buffnet.net]On Behalf Of Marty Galyean
> Sent: Wednesday, October 04, 2000 6:20 PM
> To: dakota-truck@buffnet.net
> Subject: Re: DML: Cowl Induction Vs Ram Air Which Better/How?
>
> 'ram' has two meanings. Many logically refer to cramming air into a scoop
> via
> vehicle motion as 'ram air' as Bernd notes below. But the other meaning is
> what
> automotive engineers mean by it and it goes like this. Because of the
> opening and
> closing action of intake valves, the mass of air in the intake moves toward
> the
> intake valves in a slinky-like motion. The frequency of oscillation is
> mostly
> dependent upon the rate of valve cycling. Because air is an elastic medium,
> that
> is it can compress and rarify, at any given moment the air at the intake
> valves
> can vary quite a bit in density. If you could freeze a snapshot of the air
> density in the air column in the intake from filter to valves, the pattern
> of
> dense/rarified air alternates like a sine-wave. By tuning the resonance
> properly
> on an intake the 'ram effect' is achieved when the opening intake valves
> nearly
> always see a dense wave front rather than a rarified valley. Many cars have
> tuned
> intake runners in the manifolds to help achieve this and several makers are
> looking to get the entire intake, not just the manifold, into the act.
> Can't
> remember the numbers but I recall some measurements in the neighborhood of 4
> to 5
> psi difference in density in the air-slinky in some test intake/manifold
> combos.
>
> bernd@texas.net wrote:
>
> > Considering that neither will give you any true "Ram Air", they both work
> more
> > as a Cold Air Induction system. (Ram Air won't happen unless you're
> driving
> > above 100+mph...and at a very small amount.)
> >
> > Cowl Induction collects cool air from the windshield/cowl area and the
> "Ram
> > Air" hoods just capture cold air from the vents facing forward on the hood
> > line. One thing to remember is that if you're running a Intake Tube Kit
> or the
> > factory airbox, they're both pretty much useless and work only for looks.
> >
> > - Bernd
> >
> > > Can someone explain how Cowl Induction works and is it
> > > better or equal to Ram Air.
> > >
> > > My understanding of the object of the Cowl Induction
> > > and Ram Air is to cool the engin and get colder air
> > > into the engin. Is this correct.
> > >
> > > It appears that they both cost about $400 is this
> > > correct?
> > >
> > > Any recommendations would be appreciated.
> > > Thanks
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