Re: [alfa] Twin injectors and DARPA

[webb.p@xxxxxxxxxxx]

Staged injection is very common in forced induction.   It's usually done in a speed/density system with MAP reference to change the pulse width of the injectors.   In many DIY applications, the MAP VE is set to zero for the lower half of the table for the second set of injectors and kick in when the MAP goes positive.

As to a previous comment about atomization, large injectors atomize well if positioned correctly.  Usually pointed directly at the valve.   The problem with using small injectors over large is the flyback voltage and heat generated for the large PWM they need, even in a staged environment.  Large injectors squirt more fuel in a shorter period of time.   Too large injectors cause issues not being open long enough causing the fuel to dribble rather than spray out.

Your idea of a Montreal SPICA isn't practical as it has no manifold compensation for fuel delivery.  Spica is a mechanical version of an alpha/N system that only references throttle position and RPM for delivery with thero and baro compensation.  There's no plenum reference as in a speed/density or mass/air system.

If you were seriously going to make the jump, you would have your SPICA manifold machined to accept Bosch style injectors and hook a programmable to it, or use the Weber manifold with the TWM ITB's that has everything you need.  The SPICA manifold is a better deal because you can take MAP and ECT from existing chambers where the TWM's would be alpha/N with TPS sweep reference.

This can be done at a reasonable cost.  See the Jim Kartalamakis book on throttle conversion techniques using TWM and modified SPICA manifolds.

Another ITB option commonly being used are Suzuki GSXR throttles adapted to the Weber manidold.  There are a couple of Alfa's running this setup.  One turbocharged in Sweden or Holland I think it is.

-Peter

> Will admit I'm addressing the first part mostly to Jim Steck, but hop
> right in if you have any comments.
> 
> Okay, this is all pie-in-the sky. If you're not a pie person, good time
> to hit the down arrow on the right.
> 
> Was just reading about how the new Ford GT's aluminum 5.4-liter dohc
> engine was brought up from a measly 380 hp to 500 hp by switching the
> original roots-type supercharger for a Lysholm screw-type And two
> injectors per cylinder.
> 
> Screw type make all that much difference?
> 
> Since I still consider many WWII items pretty darn high-tech forgive me
> if I haven't heard of two injectors per cylinder - Twin-Inject engine?
> One squirt earlier than the other, or just to inject at two different
> locations? Run to my nearest Alfa Dealer and get a Montreal Spica unit
> and do a little inlet manifold modifying? By also adding the Lysholm,
> should be able to get an easy 185 hp on a 2-liter.
> 
> ***********
> DARPA:
> 
> The Dec. issue of Esquire has their pick of the Best & Brightest. Since
> they started with Will Ferrell, one might have cause to go, hmmm.
> 
> Enjoyed the one on DARPA (Defense Advanced Research Projects Agency)
> especially. The one Iittle (literally) project they're working on is a
> micro atomic clock. Seems the current ones are refrigerator size. So
> they put the MEMS (microelectromechanical systems - technology) guys who
> think something is only small if you can't see it with the naked eye, in
> 
> the same room with the physicists. Apparently they did it. One scary but
> 
> very cool side benefit of the project is they needed a tiny battery. So
> they came up with one powered by sustained combustion of hydrocarbon
> fuels.
> 
> Yeah, I read the carbon part, but prefer thinking of my new wrist watch
> as being powered by a smallish hydrogen bomb.
> 
> I'm sure I must have included best and brightest on that resume I wrote
> decades ago. Figure I'll be getting the call from DARPA any day now.
> 
> So in preperation and since it is supposed to have a military use,
> thought I could sell My Idea by mentioning I didn't remember the WWII
> tanks, trucks, jeeps breaking down all that much in North Africa. And
> there sure weren't a phalanx of technicians running along behind.
> 
> Therefore, get rid of all the fancy stuff and simplify. General
> Eisenhower's driver (and, ummm, friend) probably fixed the jeep, when it
> 
> broke down, with one of her bobby pins.
> 
> So My Idea (patent pending) is to make a chip sized Multi-Use Stand
> Alone Sensor Module (MUSASM - also patent pending of course) with a
> built in radio transmitter and receiver. And I'll just borrow that hot
> little battery thank you very much. They're stuck (thinking high-tech
> JB-Weld) various places on engines - carbs, fuel pumps, blocks, oil and
> water pumps, etc. - and of course transmissions and differentials.
> 
> True, they're little electronic gizmos, but 'we'll' make them bullet
> proof. No wires, no gotta plug in to a big machine. They'll read (open
> to
> change) heat, sound, and vibration on a simple laptop and can do so from
> some distance.
> 
> None of this little piddly ass atomic clock in a smart bomb (my guess as
> 
> to where they're headed). "Let's see, I'm to go down these stairs, turn
> right at the fourth hallway, then left at the next, and it'll be the
> seventh door on the right. Oh my god, I'm one millionth of nanosecond
> behind schedule!"
> 
> No sir, My Idea won't fix the vehicles but will pinpoint where to dig in
> 
> and either replace or make a quick roadside repair. The receiving part
> of the built in radio only turns the module off and on.
> 
> Since they also consider what the eventual civilian uses will be, figure
> 
> everyone here would want their very own Alfa Analysis Kit (AAK - yes of
> course p.p.) wouldn't they?
> 
> Biba
> (Still trying to find the source of my intermittent miss)
> Irwindale, CA USA
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