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water injection
Wow, I actually understood a lot of that tech babble, Allyn. :^) I'm not too
worried about the possibility of a rough delivery curve. I just can't
tolerate any dribbling at low pressures. My intuition tells me that the key
to most of this is the spray heads. Where do I find an fine atomizing spray
head that can flow 50cc/min at 15psi or thereabouts? Help!
--
Scott F. Williams
NJ Scirocco nut
'99 Subaru Impreza 2.5 RS
Mazda 323 GTX turbo "assaulted" vehicle
Golf GTI 16v "rollycar"
ClubVAC: "Roads found. Drivers wanted."
Check out our rally team's website!
http://www.usrallyteam.com
> -----Original Message-----
> From: Allyn [mailto:amalventano1@comcast.net]
> Sent: Friday, March 22, 2002 3:00 PM
> To: Scott F. Williams; calimus@techography.net; Scirocco List
> Subject: Re: water injection
>
>
> Scott,
> Hey, you told us to poke holes...
> Keep in mind that discharge pressure of a centrifugal
> (windshield wiper) pump is non-linear.
> Change in rpm = change in pressure squared. While it is also true
> that in a centrifugal pump flow is
> proportional to motor speed, this doesnt apply since the pump is
> running at near static head
> (discharge pressure). Also in a dc brushed motor you run into yet
> another non-linearity with
> changing voltage vs. rpm. This means that with a very slight drop
> in voltage you will rapidly drop
> to below 10 psi discharge pressure.
> Yet another 'hole' is that injectors designed to work at 15
> psi may start to 'dribble' at <10
> psi.
> The best way to go proportional controller is to do some sort
> of pulsed injectors or something.
> Al
>
> ----- Original Message -----
> From: "Scott F. Williams" <sfwilliams@comcast.net>
> To: <calimus@techography.net>; "Scirocco List" <scirocco-l@scirocco.org>
> Sent: Friday, March 22, 2002 10:20 AM
> Subject: RE: water injection
>
>
> > Guys, I originally started this thread in respect to my own
> interests with
> > nitrous oxide tuning. However, anyone with a pending turbo
> project should
> > also take note...
> >
> > Anyway, I learned a few more things about doing this water injection
> > project. Speaking yesterday with George Spears, former
> president and founder
> > of Spearo Intercoolers (now sold to Turbonetics), I learned that:
> >
> > a) Mixing a 50/50 methanol and water cocktail increases the knock
> > suppression effect and may shoot inspring flame balls out the exhaust
> > between shifts. Yeeyah!!!
> >
> > b) Our 2.0l-sized motors will be happy with about 50cc/min
> water flow per
> > cylinder.
> >
> > c) In a normally aspirated situation, there is no need for a
> powerful water
> > pump. With a properly chosen flow-rated spray nozzle,
> atomization will be
> > fine. (The best system on the market, Aquamist, uses a 7bar
> pump for turbo
> > use.)
> >
> > A simple windshield washer type will work fine if the water bottle is
> > located close to the engine. If not, then two of these pumps in
> line will
> > work fine. Again this is for normal aspiration. Turbo guys will need
> > something more powerful.
> >
> > d) The real key to this job seems to be finding the correct
> spray nozzles.
> > They have to atomize properly at about 15psi and flow just 50cc/min. The
> > research continues!
> >
> > P.S. If I do this, I'll probably base my system off of the Spearco
> > Injetronic system. By tapping into the tachometer signal, the
> system varies
> > the amount of voltage sent to the water pump based on rpm. So,
> actuation is
> > not just an on/off affair. Nice!
> > --
> > Scott F. Williams
> > NJ Scirocco nut
> > '99 Subaru Impreza 2.5 RS
> > Mazda 323 GTX turbo "assaulted" vehicle
> > Golf GTI 16v "rollycar"
> > ClubVAC: "Roads found. Drivers wanted."
> >
> > Check out our rally team's website!
> > http://www.usrallyteam.com
> >
> > > -----Original Message-----
> > > From: Brian Haygood [mailto:scirious@hotmail.com]
> > > Sent: Thursday, March 21, 2002 12:31 PM
> > > To: Scott F. Williams; Scirocco List
> > > Subject: Re: water injection
> > >
> > >
> > > Hey Scott, I have a great idea! Why not get a NOS bottle
> and fill that
> > > with water for your injection system. That would be PHizAT!
> Then you
> > > would have some real respect wherever you went (OK, maybe
> not from anyone
> > > who has enough brains to tie his own shoes, but the boy
> racer/civic types
> > > would love it).
> > >
> > > ha ha ha ha ha. I amuse myself today.
> > >
> > > I'd also like to share with everyone that, having graduated
> in December I
> > > went from professional student to officially unemployed, but
> today I got a
> > > real job. They even pay money, not just course credits or
> > > something. It's
> > > a good day. I'm looking forward to calling in sick to work on my
> > > Scirocco,
> > > so I can officially be just like everyone else on the list. :)
> > >
> > > On a less sarcastic note, I don't see why water injection
> wouldn't do the
> > > trick for you, Scott. Could you just use the supply of
> windshield washer
> > > fluid and keep that cleaned up and filled with distilled water or
> > > something?
> > > I guess that depends on how much NOS you plan on spraying.
> If you need a
> > > good water bottle, you might look the later cars. My '95 Passat
> > > and '00 GTI
> > > both have 5 liter washer bottles, with the motors nicely nestled
> > > inside/alongside them.
> > >
> > > For spray nozzles, maybe you can use needle jets from
> carbeurators? There
> > > is certainly a huge variety of those in the world, and some at
> > > least can be
> > > installed in a threaded hole in the T-body's. They would
> probably drip a
> > > few drops after turned off, but that's probably OK, isn't it?
> > >
> > > You would drive yourself nuts trying to rig some kind of
> injector on each
> > > body, I think, especially when you have already squeezed in
> fuel, NOS, and
> > > pressure taps to each body.
> > >
> > > BH
> > >
> > >
> > > ----- Original Message -----
> > > From: Scott F. Williams <sfwilliams@comcast.net>
> > > To: Scirocco List <scirocco-l@scirocco.org>
> > > Sent: Thursday, March 21, 2002 8:46 AM
> > > Subject: water injection
> > >
> > >
> > > > Hey, I think I'm about to blaze some new trails here, but I
> figure I'll
> > > ask
> > > > anyway. Does anyone on the list have any experience with water
> > > injection?
> > > > I'm rethinking my plans for a fuel cell holding racing
> gasoline for use
> > > when
> > > > I activate my nitrous system.
> > > >
> > > > There's a lot of redundant plumbing and electrical controls
> > > that I'd have
> > > to
> > > > rig. -more weight and more stuff to go wrong. I'm thinking
> that a well
> > > > implemented water injection system would do the trick just
> > > fine. I figure
> > > > that I could activate in two situations: a) via whatever
> signal triggers
> > > the
> > > > nitrous, and b) whenever knock is detected.
> > > >
> > > > I could mount the water tank pretty much where ever I'd like. I
> > > figure I'd
> > > > put it somewhere around the battery (in the back) with a
> couple of small
> > > > windshield washer pumps run inline to keep the pressure and
> flow up. The
> > > > minor plumbing challenge would be rigging a distribution
> block and lines
> > > to
> > > > each throttlebody. And, of course, I'll have to find some
> spray nozzles
> > > with
> > > > a nice atomization pattern and the correct flow.
> > > >
> > > > Babble... babble... I'm on Spring Break!!!! :^)
> > > > --
> > > > Scott F. Williams
> > > > NJ Scirocco nut
> > > > '99 Subaru Impreza 2.5 RS
> > > > Mazda 323 GTX turbo "assaulted" vehicle
> > > > Golf GTI 16v "rollycar"
> > > > ClubVAC: "Roads found. Drivers wanted."
> > > >
> > > > Check out our rally team's website!
> > > > http://www.usrallyteam.com
> > > >
> > > >
> > > >
> > > > _______________________________________________
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> > > > Scirocco-l@scirocco.org
> > > > http://neubayern.net/mailman/listinfo/scirocco-l
> > > >
> >
> >
> >
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