Neil,
I
have flown an Eaton MP90 4th gen super charger
for a little over 500 hours. No intercooler with the super
charger. Turbo FWF is in the works and will have an
intercooler. I needed a wider compressor map at a lower PR
for takeoff than the TO4-50 . I ended up purchasing a Garret
GT3076R w/ Tial 1.06 SS housing. I would have preferred a
journal bearing turbo but this one is ball bearing.
Do
you have a reason for added EGT’s to the fueltech vs an
aircraft engine monitor / efis?
Bobby
From:
Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net]
Sent: Saturday, December 08, 2018 2:47 AM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: Hey Neil,
Bobby,
Yes I have the wide band 02, but when I
used the microtech which was the reason I ditched it it was to
me impossible to tune properly. Then Microtech refused to
answer phone calls or were gone to a drag race somewhere---
all queries were to be done by internet. With microtech as I
said before the mixture knob did nothing except occupy another
hole in the dash. EGTs in excess of 1850 degrees were easily
reached.
Long story short I left Microtech and bought the fueltech.
Much easier to tune and actually have backup as required. Did
not add an EGT as nothing seemed to change with the microtech,
so simply slept better not knowing what the EGT's actually
were.
Can add EGT to the fueltech but another $1000 AUD. May have
to go that way as intend to get to 8000 RPM if required
Today at low 30's degrees my water was on the thermostat at
95 degrees C and oil around 90. Saw your temps and had a
heart attack until I realised you are farenheit.
What turbo do you run and have you an intercooler?
Will get to check out the ag turbos shortly as there are
hundreds of them around here. Will get to weigh one shortly.
Neil.
Neil,
Do
you have a wideband O2? I have to run in the low 11’s at
full power and under boost for takeoff. 7000 rpm / 30-48”
MP to keep egt’s around 1600F. Typical cruise between 4800
– 5200 rpm / <30 “ MP with F/A 15.8:1 brings EGT’s
into the 1500’s. With an intercooler I would expect F/A in
the 12’s will keep egt’s below 1600 but that’s just a
guess. I have seen EGT’s at or below 1475F on cold days at
altitude. The only time I run stoichiometric is in the
pattern and low MP.
Information
from Pro Formula Mazda
Engine Vitals: Exhaust Gas
Temperatures Exhaust Gas Temperatures (EGTs) are the
second most important tuning and troubleshooting channel
next to Lambda. EGTs reflect on the injector balance between
the front and rear rotor Reflects misfires through high
readings accompanied by normal lambda Decline in engine
performance can be evidenced by the rate of temperature
acceleration between the rotors during a long pull – gapping
Emphasis needs put on the condition of the EGTs – low
reading sensors are beginning to fail. In order to have an
accurate assessment of the performance, EGT sensors must be
replaced often. Generally, one EGT sensor is used per rotor.
One sensor bung should be welded on the each the outer
exhaust pipes 3” from the header flange (the center pipe
usually does not receive a sensor). The sensor depth should
be enough to where the tip of the sensor is in the
centerline of the exhaust flow. Operational Range: Front
Rotor: 1450F – 1600F, Rear Rotor: 1400F – 1550F
Engine Vitals: Lambda
Lambda is the measure of the amount of
oxygen in the exhaust stream. The value expressed is a
percentage of the stoichiometric air/fuel ratio 14.7:1.
Air/fuel ratio can be calculated by
multiplying the lambda value monitored by data system by
14.7
(ex: .90 Lambda translates as (.9 x 14.7 =
)13.23 Air/fuel ratio
Operating Range = .87 - .91, aim for
.90
Bobby
From:
Rotary motors in aircraft [mailto:flyrotary@lancaironline.net]
Sent: Tuesday, December 04, 2018 1:30 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: Hey Neil,
Ok, interesting stuff, but how do you keep the exhaust temp
below 1600 degrees without losing a lot of power? I no
longer have an EGT as it just worried me with 1800 degrees
and the cost of burnt off egt probes. From memory 1600
degrees goes out the window at about 6000 rpm or less?
Neil.
Hi
Andrew, I know next to nothing about turbo technology so
have stayed clear of them; IIRC this is the first time
I’ve heard of using a turbo from the agricultural
industry and advice to stay clear of the automotive type
... seems to make sense – tractors use turbos that last
for decades.
Jeff
(13B, RD1-C, 144 hrs)
From:
Sent: December-03-18 5:14 AM
Subject: Re: [FlyRotary] Re: Hey Neil,
Neil, Type Turbo selection
Into search of flyrotary archives, you’ll get about 30
posts from 2002 to 13 that are worth reading, other
searches will give more.
Basically you want something the size
of a T04 60-1, keep the A/R >1, something like 1.15
or 1.30
T04’s are plentiful from all the
older diesels like 2wd tractors from last century. you
probably got a few parked up around you that will still
be servicable. If you can find one without a intercooler
on it, chances are that it might have the right
compressor. Otherwise they are easy to change.
Steer clear of automotive turbo’s,
they will overspeed at altitude & disintegrate, need
waste gates & blow off valves. Stuff thats not
required on an aeroplane.
When installing. Put a normally open
solonoid valve in the oil supply line. Allows you to
close the oil supply if the turbo blows its seal.
Always bugged me why turbo shops
charge so much for such a simple part.
--
Homepage: http://www.flyrotary.com/
Archive and UnSub: http://mail.lancaironline.net:81/lists/flyrotary/List.html