Frans=0AI think you are right, much more logical conclusions than mine !:-)
=0AAgree about the Jabiru also, sad but geared and liquid cooled will alway
s have a =0Aperformance advantage. More complication too of course but a mo
re sensible =0Acompromise I think.=0Aregards=0AGraham=0A=0A=0A=0A=0A_______
_________________________=0AFrom: Frans Veldman <frans@privatepilots.nl>=0A
ject: Re: Europa-List: Re: JABIRU 3300 BRAND NEW OVER TEMPERATURE DURING
epilots.nl>=0A=0AOn 04/15/2011 10:17 AM, GRAHAM SINGLETON wrote:=0A=0A> To
a certain extent the same thing happens with Rotax so the front=0A> cylinde
rs get more fuel than the rear at some throttle settings, drops=0A> of fuel
don't turn corners the same as air molecules!=0A=0AI believe the "problem"
with the Rotax is of a different nature. There=0Aare two carbs, and the in
let pulses are not equally distributed. Each=0Acarb will see two inlet puls
es in sequence, then followed by a long=0Apause when the cylinders on the o
ther side (fed by the other carb) have=0Atheir respective inlet pulses.=0AA
fter the pause, the flow of fuel inside the nozzles is stalled. With=0Athe
first cylinder breathing, the fuel has to start moving again, and=0Athe sec
ond cylinder has the benefit that the fuel is already up to=0Aspeed. So the
second cylinder in the sequence receives a slightly richer=0Amixture.=0AA
solution can be to use a bigger bore balance tube. Some Italian=0Acompany i
s selling a pair of manifolds and balance tube for this=0Apurpose, and the
manifolds have already the bosses in them to mount fuel=0Ainjectors for fut
ure upgrades (and using the carbs as fuelless throttle=0Abodies and backup
in case the EFI fails).=0A=0AOk,the subject was "Jabiru". To keep it in the
subject: After the long=0Alist of problems and disadvantages, can anybody
enlighten me what the=0Abenefit is of the Jab over the Rotax? (I assume the
re must be one, why=0Aelse would anyone bother to install one?)=0A=0AFrans
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