David Doshay wrote:
How much would it cost to convert the O-360 in my Cessna 172?
I can't offer you a solution to convert your C-172 at this time.
Currently our liquid cooled conversion is not certified and therefore
cannot be used in certificated aircraft. We are moving forward with
certifiying the liquid cooled modifications which we hope to complete by
the end of 2001. Even once we certify the engine mods, converting a
C-172 would require the development of a new cowling arrangement and as
well as finding a location for the radiator.
Of course we are looking forward to the day when we have liquid cooled
C-172s flying, however we are still at least a couple of years away from
achieving that goal.
I am attaching a complete overview of our Cool Jugs conversion below to
help address any other questions you may have.
Thanks,
David
Our Cool Jugs conversion kit is just that - a kit that converts
virtually any wide or narrow deck O-360 or O-540 series Lycoming engine
to liquid cooling. This includes carbureted, fuel injected,
turbocharged and turbo-normalized engines. Running liquid cooled the
cylinder head temps are maintained at a steady 190 deg F (+/- 5 deg F).
Cylinder to cylinder temp variance is essentially eliminated as all
cylinder temps run within 2 deg F of each other. Shock cooling and
heating are *completely* eliminated.
Cool Jugs is a complete, bolt-on kit that will allow a conventional air
cooled O-360 or O-540 parallel valve Lycoming engine to be converted to
liquid cooling. The result is a fully liquid cooled aircraft piston
engine. An engine that operates at a stable 190 degF without any* need
for airflow over or through the engine compartment.
The Cool Jugs liquid cooled conversion requires absolutely no internal
engine modifications! In fact no existing reciprocating/moving
components are changed in any manner. The conversion creates only one
additional moving part - the coolant pump, which is grear driven via a
standard accessory pad.
Normally aspirated engines can be run at peak lean EGT or even at 50
deg F lean of peak EGT at *all* power settings and RPMs providing you
with substantial fuel savings and *more* power. You also have the
option of using the higher compression 9.0:1 pistons for even greater
power. The stock O-360 engines typically run 8.5:1 pistons. Our dyno
testing shows that an O-360 with 9.0:1 pistons puts out 195HP at 28"Hg
manifold pressure at peak EGT resulting in a fuel burn of 11.7gph
without even a hint of detonation. Keep in mind this is at sea level
pressure. The best an air-cooled O-360 can do is around 12.5gph at peak
EGT, 28"Hg manifold pressure and that's with occasional detonation
occuring.
In fact as part of our dyno testing we ran a detonation survey on our
liquid cooled O-360 in an attempt to discover if and under what
conditions detonation might occur. What we found was that we could run
the engine at wide open throttle (28"HG manifold pressure) at peak EGT
and even at 50 degF lean of peak EGT and load the engine down to 1600
rpm (as much load as the dyno could apply) and left it there for as
long as 20 minutes without so much as a hint of detonation. That's
practically the equivalent of running wide open throttle with a
feathered propeller.
The reason you get more power when running at peak lean EGT is because
you aren't cooling the combustion mixture with excess fuel so you get
more thermal energy and in turn more power. You absolutely don't have
to be concerned about 'burning up' our liquid cooled engine running at
peak EGT or even 50 deg F lean of peak EGT - even at sea level manifold
pressure. In fact running at peak EGT at all times will actually
improve the life expectancy of the engine since it prevents the buildup
of lead deposits.
For reference a typical air-cooled O-360 running at wide open throttle
(28"Hg) at full rich will consume over 18gph. Even at altitudes above
3000' when leaning is possible, an air-cooled O-360 will consume more
fuel because it is (a) running much hotter, around 380-400 degF and (b)
due to uneven cylinder temps, you can only lean until the hottest
cylinder starts to misfire.
You should consider that installing a liquid cooled engine in any
airframe will require re-design of the cowling since our engine does
not require any* airflow through the engine compartment. You should
also consider where you might be able to locate the radiator. You will
need approx. 5000 CFM of cooling air for the radiator. A well designed
low drag radiator installation should incorporate a relatively small
air intake and a ducted air plenum to the radiator that provides for at
least a 3-4 times expansion of the air intake.
*Note: A small volume of 'breather' air is recommended for cooling the
alternator and generally keeping the engine compartment ventillated
against any buildup of fumes. You may also need separate cooling air
for the magnetos and possibly the fuel pump.
The radiator for the O-360 engine is fairly small (14" h x6" w x6" d)
and could be mounted in the engine compartment or remotely depending on
the airframe. We can have a custom radiator built to meet your needs.
A properly designed installation would be to have no more than a 24 sq"
intake and a ducted plenum that gradually expands to meet the radiator
face which is actually 12"x6" (72 sq"). The expansion rate should be
limited to 15 deg in order to prevent undesirable turbulence from
developing within the plenum. This may in some cases result in an
expansion plenum that is too long for a given airframe installation to
be practical. In such cases internal vanes can be incorporated in the
plenum in order to spearate and maintain a 15 deg expansion path.
For more information take a look at the following site:
http://www.inforamp.net/~raac/CoolingSystems/CoolingSystemsIndex.HTML
Weight
A typical conversion will add an additional 30-35 lbs to an engine
installation. This weight includes all of the components, radiator,
hoses and coolant. The coolant is the largest percentage of additional
weight since water (glycol/water mix) weighs 8lbs/gal and the typical
system requires 2 to 2.5 gallons of coolant. A significant portion (12
lbs) of this weight can be offset by installing a lightweight starter.
Given the potential performance improvements both in terms of drag
reduction and engine life expectancy we feel confident that the
additional weight of a liquid cooled engine will be more than offset by
its benefits.
While we can't address the potential of additional weight savings in
every airframe we can tell you that in converting a Piper PA28-180
to liquid cooling we expect to offset a significant portion of the
additional weight with a *much* lighter cowling. The redesigned cowling
will be built from carbon fiber and we anticipate that it will be
approx. 10-12lbs lighter than the original cowling. This savings along
with the removal of the aircooled baffling and changing the induction
air box will result in an additional 7-8 lbs of weight savings.
Overall, with the lightweight starter (12lbs), cowling (10lbs),
air-cooled baffling (3lbs) and induction air box changes (5lbs) we have
managed to achieve 30lbs of weight savings - virtually offsetting all
of the weight gain of the liquid cooled O-360.
Certification
Currently the Cool Jugs liquid cooled conversion kits are not FAA
certified and are for experimental use only. Liquid Cooled Air Power
is persuing FAA certification and are hoping to achieve certification
by late 2001.
Pricing
Our Cool Jugs conversions are available for both the O-360 series and
O-540 series engines.
The Cool Jugs conversion kit includes:
. New nitrided cylinders/valve train
All valve train components are New FAA-PMA
approved parts:
o Intake and Exhaust valves
o Valve seats
o Valve Springs
o Rocker Arm bushings
o Top end gasket set
o Rocker box covers
. Coolant manifold & Coolant pump
. Thermostat housing & thermostat
. Engine hoses
o Steel braided Aeroquip TSO C53a 1000psi test hose
o AN fittings
. Custom designed Coolant system monitoring gauge
and transducers.
o Coolant Temperature
o Coolant pump output pressure
o Low Coolant warning
We offer a 7 year/3000 hour pro-rata, limited warranty on the major
components which include the liquid cooled cylinders, valve train
(limited to the intake & exhaust valves, valve seats and springs) and
the coolant pump.
We may extend the calendar limit of our warranty as our field
experience grows.
Our conversion kit does not include a radiator or engine to radiator
hoses since each airframe's installation requirements are unique.
The O-360 kit is priced at $12,995 and the O-540 kit is priced at
$18.995
We will have kits ready to ship in Jan '01. We offer field support to
assist with installation and on going support.
If you email me your address we will send out a more complete brochure
on the conversion kit.
Thank you for your interest. Please don't hesitate to contact me if you
have any additional questions.
Sincerely,
Bob Atkins
Liquid Cooled Air Power, Inc.
David Doshay wrote:
Note the price is near the bottom. Gotta be real interested in liquid
cooling to pay this much!!
Cheers,
David
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