> > > > <Big Snip>

 > > >
 > > >
 > > > That brings me to the next question, what are the injector
specifications
 > > > that I should use if I don't purchase replacement mazda injectors?  I
 > know
 > > > they should be of the high resistance > 13 ohm to work with Tracy's
 > system
 > > > but I'm not sure about nozzle flow rates.  Also, are the primary and
 > > > secondary injectors different?  Related to the injector diffuser
 > question,
 > > > if you replace the injectors with a different make should they work
 > with and
 > > > fit into the mazda diffuser?
 > > >
 > > > Del Johnson - Another Glastar builder
 > >
 > > Tracy says the engine needs up to 18 gallons an hour at full power.
 > >
 > > BTW least you think that is high you would be wrong. 200 HP aircraft
 > > engines also need that kind of fuel flow at full power.
 > >
 > > I would say 20 gallons per hour to be on the safe side. Since there
 > > are four injectors that is 5 gallons per hour or 30 pounds per hour
 > > per injector. I'll be using the stock Mazda 88-91 turbo injectors. At
 > > least initially.
 > >
 > > Paul Lamar
 >
 >
 > > List,
 > > Summit Racing carries Ford 30lb injectors (set of 8, of course) for
 > $210.  Maybe it would be worth just buying new injectors instead of
 > fooling around with the old ones.
 > >
 > > Ken Powell

 What was the pressure required for 30# flow?

 For those of us assembling engines from parts this is the way to go.  We
 should pair up on these sets of 8 as $105 /4 injectors is a good price last
 time I checked.  Anyone in the Portland, Oregon area needing 4 injectors
 besides me?

 Also, just checking calculations here, you want to size your injectors for
 your engine at 80% of rated capacity.  That is if you need 30 pph (per
 injector) your injector should be rated at 37.5 pph.  If we use 0.6 pounds
 of fuel per hp per hour (Max rich mixture):

 200 HP * (0.6 #/HPhr) = 120 #/hr    equals 30# injectors

 Correction for 80% duty cycle:  30#/80% = 37.5# injectors

 For 30# injectors this back calculates to 160 HP.

 Also 2, if you are planning to be able to fall back to 2 injectors per the
 capabilities of Tracy's EC2 you need to decide if (in the above example)
 100HP is enough to get you home.  If you need more than that, run the calcs
 for two injectors at minimum HP and 80% duty cycle.  A typical RV can
 easily make it home on 100 HP if you don't have to climb faster than a
 C-150 on a hot day.  OTOH I'd be looking for the nearest airport.  A
 Glastar might be fine on 100 HP, but, you need to ask the Glastar experts
 for that.  Tailwinds, I don't have a clue, Jerry?

 > Mike

A TW will cruise nicely with 100 hp. The first Tailwind flew with
an 85 hp  Continental.  Top speed was 150 mph.  At that time its
performance was revolutionary.   Got a lot of press.  Lets see, that
was fifty years ago.  Any modern two seaters out there that can do
better on 85 hp?       Of course, the fun begins with 150 hp and
just gets better and better until someday soon,  when a 220 hp P
Ported rotary will be tied to the front end.  As long as I'm
boasting, bragging and issuing hard to believe facts,  here is
another:  at the time of the first flight my VFR TW will have cost
less than $20,000.     Think about it.      Jerry

 
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