Paul,
I have only recently joined your newsletter so bear with me if I am
revisiting subjects that have already been discussed.
I am in the process of designing and building an experimental amateur built
airplane and am intrigued with the possibility of using a rotary engine.
My initial observations at this time are that the Renesis engine holds
significant promise as an aircraft engine but in order to achieve that
success the engine must weigh approximately 80 lbs. less than currently
configured. In order to achieve that weight reduction it is necessary to do
away with three large pieces of cast iron. Mazda has found a way to replace
those pieces of cast iron with aluminum alloy in their 16B engine. It can be
done. With all the brain power available on this site, we should be able to
solve this problem. Perhaps the answer is in hypereutectic aluminum alloy. I
do think that none of us is as smart as all of us.


The Eltings

You have a lot more to deal with than just the engine.
There is the cooling system the gear box and the prop.
The big question is how much HP do you need?

Or.................

What airplane are you building?

Paul Lamar


Paul,
You may have misread my email. I am not looking for an 80lb. rotary engine,
My intent was to configure a Renesis engine with components to achieve a
total weight of 210 lbs. excluding the prop and mount. My reasoning is as
follows:
    Base engine wt.- 109 lbs. (based on the image on your website)
    
    Aluminum flywheel - 7 lbs.

    PSRU - 35 lbs.

    Starter - 7 lbs.

    Alternator - 7 lbs.

    Hydraulic pump - 9 lbs.

    Exhaust system - 17 lbs.

    Radiator, oil cooler, Oil filter, Oil tank, and fluids - 21.5 lbs.

As opposed to the Mistral G200 engine, based on 1300 cc Mazda engine,
weighing 291 lbs. My comment was that it was achievable, without
extraordinary measures, to build an aircraft engine, without turbo charger,
of equal or more hp and have it weigh 80lbs. less.

The aircraft I intend to build is of my own design. I cannot adequately
describe it to you in an email, however I can say it looks remarkably like
an Eclipse 400 with a tractor engine in the front rather than a jet on the
back.

I need an engine that is small, light weight and produces approximately 150
to 190 hp.

Thank you for your reply.

I value your advice.

Doug


Yes I did. Sorry Doug.

P-port the RX8 engine and you are sure to get 190 HP with
a simple and light weight intake system. 190 HP can be had
at 7500 RPM with out the p-port but you will need to "port" the
engine and get the intake manifold exactly right.

Why the 9 pound Hydraulic pump? The 109 pound engine has the engine oil pump
in it.

The exhaust system can be much lighter if you use .035 thick Inconel.
Inconel is .3 pound per cubic inch. So a square in of .035 thick sheet would weigh
.01 pound.

Paul