>>>> Do you think the Kinsler nozzles would work in the RX8 intake
>>> manifold
>>>> injector holes or do they have to be in the main air stream?
>> Karibian
>>>>
>>>>
>>>> I think they have to be in the air stream.
>>>>
>>>> Paul Lamar ...No rotor no motor.
>>>
>>> Perhaps an e-mail or call to them would be beneficial.
>>> They have been very good at problem solving for our
>>> race engines, without a sales pitch. Every system sent
>>> to them for rework and calibration, has come back so
>>> well set up that we hardly turned a screw upon installing.
>>> Archie
>>>
>>>
>>> Karibian,
>>>
>>> I would suggest downloading the catalog and looking at the various
>>> nozzles shapes and sizes they offer. If you can find a shape and
>>> size similar to the EFI nozzle on the RX8 engine, I don't see why
it
>>> should not work.
>>>
>>> The key thing is that it should spray fuel into the runner the
same
>>> way the stock nozzle does -- not spray it onto the runner wall
>>> because it's too short or whatever.
>>>
>>> The other thing is how you will thread it in. It may not be the
same
>>> size hole or thread. If the existing hole is smaller you may be
able
>>> to enlarge it and rethread it so the Kinsler nozzle will fit.
>>>
>>> Regards,
>>>
>>> Gordon.
>>>
>>
>> Gordon,
>>
>> If the nozzle is constantly spraying then at low idling speeds some
>> fuel is
>> getting sucked out with the exhaust during over lap. I can imagine
>> that at
>> higher speeds this is not happening perhaps as much if at all. What
>> do you
>> think the BSFC will be compared to EFI in light of the fact Mazda
>> choose the
>> later in Lemans. They were concerned to get the best BSFC since
> it is an
>> endurance race. Mistral and Tracy both say that timing of the
>> injection is
>> critical for good BSFC.
>>
>> In either case I want the injector right on the housings so maybe
>> this isn't
>> an issue. I am trying to design a way I could test both systems
>> using the
>> same injector boss.
>>
>>
>> Doug
>>
>> Doug,
>>
>> Mounting the injector right on the housing sounds like a good idea.
>> It will maximize the evaporative cooling effect of the fuel on the
>> air charge. I guess you will attach the bosses to the p-port tubes
>> that go in the housing?
>>
>> About the BSFC, off the top of my head I don't see why the constant
>> flow nozzles should be at a disadvantage. Maybe at idle, like you
>> say but how much time do you spend at idle?
>>
>> I could be wrong. Maybe the rotary has some peculiarities that
could
>> make timed injection better. But at a steady rpm and power output I
>> don't see any advantages with timed injection.
>>
>> If we think about the flow in the intake manifold, it is pulsed not
>> steady, coinciding with the rhythm of the intake cycle. So the flow
>> coming out of the nozzle will be pulsed also, becasue the air
>> flowing across the nozzle pulls the fuel through the nozzle. As the
>> air mass flowing across the nozzle slows down, the flow from the
>> nozzle will slow down. As it accelerates, the flow from the nozzle
>> will accelerate.
>>
>> So even though fuel is flowing constantly, the amount of fuel flow
>> coming out of the nozzle will vary with the pressure pulses in the
>> manifold.
>>
>> Of course only testing will give you the real answer.
>>
>>
>> Regards,
>>
>> Gordon.
>>
>>
>> Doug,
>>
>> I found a needle valve that should work nicely. It is made by
>> Swagelok and smallest size is 1/8 NPT which should be good. Orifice
>> size is 0.08".
>>
>> it uses a toggle handle to pull the needle out and open the valve,
>> but we can toss that handle and attach a cable right to the needle.
>> As you pull the cable the needle comes out and flow increases. This
>> is perfect because increasing the flow on the return line makes the
>> mixture leaner.
>>
>> So pulling the calbe makes the mixture leaner, just as it should
be.
>> If you have a nice Vernier cable, you can make very fine
adjustments.
>>
>>
>> Regards,
>>
>> Gordon.
>>
>>
>>
>>
>> Regards,
>>
>> Gordon.
>>
>> Interesting idea.
>>
>> The only problem I see Gordon is it does not have a long needle.
>> Hard to tune with something that moves only a fraction of an
>> inch from full off to full open even with a vernier.
>>
>>
>> Paul Lamar ...No rotor no motor.
>
> Gordon,
>
>
>
> Yes we use Swaglok stainless fittings throughout our equipment. It
is a
> beautiful valve you have shown. Only one small problem. It is not a
> metering valve. It is designed to open the flow rapidly and is
basically
> an on/off type of valve. The design point is based on convenience of
> opening it and flow characteristics. A very common type.
>
> Needle valves are short and the fuel moves perpendicular to the axis
> of the
> needle movement. The total travel from slightly open to full open is
a
> function of the fuel port size. The diameter of the needle is larger
> then
> the port size.
>
>
> Paul you can make the needle 10 inches long and it is not going to
> change
> these characteristics:) Excuse me but you are trying to redesign the
> horse
> to fit the cart.
>
> Think how an idling needle is used to fine tune the air flow in a
carb.
> Sort of similar but the ratio of the intake throat diameter compared
> to the
> idling needle is huge. In a metering valve the needle and the throat
> (port) are closer to the same.
>
>
> Adjusting a needle valve works very Vernier like. On your console
> just use
> a cable designed to transmit torsional movement. Sure there will be
> a little
> flex depending on the quality of the cable you choose and the
> resistance of
> the O-ring in the valve, but that flex is a constant that the pilot
can
> compensate for it.
>
> For an illustration of how they work go here.
>
> http://www.hoke.com/products/valves/meter/v_meter.htmBTW
>
> Click on catalogs and download the PDF on the 1600 series. On the
second
> page is a good illustration. Sorry I have downloaded the PDF file
> but I was
> not able to capture that illustration.
>
> This particular company's products are not hoke despite the name:)
> They are very expensive but very accurate. Do a google search on
needle
> valves and you will find many companies out there.
>
> Cheers
>
>
> Doug
>
> I understand how they work. Our leaning cable moves rapidly
> from one end to the other three inches away just like the throttle
> cable. Making the needle the same length means we can make gross
> adjustments rapidly from full off to full on and fine adjustments
> with the vernier. The leaning cable knob has a button on it. You
> push and hold the button in to release the vernier and make the
> gross adjustment. Release the button and then the vernier works
> again. I have one on my C182. Next time you are in the states
> flying around rent a Cessna with a vernier knob instead of flying
> your C150 or stop by my hangar :)
>
> Paul Lamar ...No rotor no motor.
>
> Doug,
>
> What about this? This is a true needle valve from Parker. The graph
> showing flow looks very linear.
>
> The only thing with this valve is it adjusts by turning, so you
> would have to have a cable that works by turning not push-pull.
> Nothing wrong with this approach.
>
> An ideal valve would be this but with a quarter turn lever, but
> there does not appear to be such an animal in existence.
>
> I still think that Swaglok valve might work. True, it's meant for
> quick opening, but it's still a needle valve. If that pin is lifted
> up a little at a time, the flow increase should be linear. It looks
> pretty much the same as the Parker valve in cutaway.
>
> The only thing is you would have to replace that Nylon lever with a
> metal lever so you can hook up your Vernier cable.
>
> Regards,
>
> Gordon.
Gordon
Yep, Parker is another good company. That should work.
Doug
What do you guys have against this idea? What is wrong
with it?
Paul Lamar
Not a thing. I see no reason it won't work. And work well...
Steve Webre
Broussard LA
N3812V
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