Mazda engines with Ross redrive
Phil Chaddock
Friend is eager to put "180hp" mazda rotary with a Ross planetary gear
reduction on his homebuilt.
Anyone have any experience with either component or the combo to share?
Don't want to see buddy get burned.
Thanks, Phil
Jim Root
I can't find it right now, naturally. But I just read an article in
recent Kitplanes about a guy with a mazda rotary in (I believe) a RV-4
If I can find the darn thing I'll post the issue info.
--
:{) Jim
**************************************
* http://home.earthlink.net/~jaroot/ *
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Remember its better to be on the ground wishing you were in the air,
than in the air wishing you were on the ground...
old VFR saying, source unknown.
Bruce A. Frank
Phil Chaddock <pcha...@mts.net> wrote:
>Friend is eager to put "180hp" mazda rotary with a Ross planetary gear
>reduction on his homebuilt.
>
>Anyone have any experience with either component or the combo to share?
>
>Don't want to see buddy get burned.
>
>Thanks, Phil
He couldn't make a better choice for an auto engine FWF.
Bruce A. Frank
Tony P
I have a question about that "180 HP." Figures I've seen seem to
show that only the highly-modified, expensive rotaries are producing
that, and the more low-key ones are producing comparable to a 160 HP Lyc
O-320.
Not to discourage it, because I think it's a really good combo
though the ones I've seen were pretty loud (they were prototypes though).
Bruce A. Frank
The definitive book on the rotary is simply called "ROTARY ENGINE"
by Kenichi Yamamoto published by Toyo Kogyo Co. Ltd. (Mazda) in
1969. This is a highly technical book chronicling the development of
the wankel by Mazda. Kenichi is an engineer and has risen to be CEO of
Mazda.
Another technical book on the Wankle rotary engine is; "The Wankel
RC Engine Design and Performance" by R.F.Ansdale Published by A.S.
Barnes & Company Lib of Cong 69-18692
=======
Good info!
Bruce
Frank van der Hulst
> > Friend is eager to put "180hp" mazda rotary with a Ross planetary gear
> > reduction on his homebuilt.
Charles K. Scott
In article <3265A...@mts.net>
Phil Chaddock <pcha...@mts.net> writes:
> Friend is eager to put "180hp" mazda rotary with a Ross planetary gear
> reduction on his homebuilt.
>
> Anyone have any experience with either component or the combo to share?
>
> Don't want to see buddy get burned.
>
> Thanks, Phil
Recently, Tracy Crook mounted exactly this combination in his RV-4. He
had to do a number of cooling modifications in order to get it to stay
cool even under high power climbs. One of the tricks was to route some
coolant through a run of tubing that goes through the oil pan.
Then there's Any Venable who mounted the 13B/Ross drive in his
Christavia Mk IV and reports no problems. He got around the exhaust
heat by keeping the thermal oven on the engine. This incurs a weight
penalty of 40 lbs. but allows mild steel tubing for the exhaust system.
The engine is almost impossible to blow up. It almost literally cannot
fail while running but can degrade to so little compression that you
won't get it started again if the rotor tip seals are not kept
lubricated. Another problem is that the oil provides around 30% to 40%
of the overall engine cooling so an oil cooler isn't just added
protection, it's an absolute necessity.
Back to the rotor tip seal lubrication. This is a little known but
potentially problematic situation. The rotors tip seals are normally
lubricated by a metering oil pump which draws from the oil pan. The
oil isn't what you would normally want injected directly into the
combustion chamber as it builds up into a thick crust of carbon after a
while. It's a compromise (isn't everything?) between needing
lubrication and having a ready source of oil. Mazda thought about
using a seperate oil tank filled with oil specially designed for the
purpose (perhaps ashless oil) to feed the metering pump but in the end
decided that the driving public would probably forget to fill it, or
fill it with ordinary oil. They're probably right. But what we end up
with is a system using a tiny pump with a tiny chain driving it.
Racing Beat, a Mazda engine racing company in CA, and Lou Ross both
recommend you don't use the metering oil pump for safety reasons; ie.
what if it breaks?
They recommend you just delete it and mix the necessary oil with the
fuel. That was the final kicker for me. I just couldn't see myself
carrying around a case of special oil and having to calculate how much
has to be added to each tank every time I refilled. It might not have
been so bad had I had a low wing monoplane, but I don't. I'll have to
be standing on a ladder everytime I refuel.
Anybody want to buy a rebuilt 13B? Bargain pricing. :-)
Corky Scott
Howard Jones
Bruce A. Frank (BAF...@postoffice.worldnet.att.net) wrote:
: The definitive book on the rotary is simply called "ROTARY ENGINE"
"The Wankel Engine, Design, Development and Applications"
Jan P Norbye.
published by Chilton. ISBN 0-8019-5591-2
Library of Congress cat card 73-161624.
also worth a read.
--
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Howard Jones, (how...@perth.dialix.oz.au) _--_|\
66 Towton Way, Langford 6147, Western Australia / \
Freeflight Aeromodeller,Tyre Kicker & Current Pilot! *_.--._/
Corby Starlet Plans #279....SAAA 4330, Editor "Western Flyer" V
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Glenn Scherer
Charles K. Scott wrote:
<snip>
Corky, it's been 15 years since I had my 13B apart, so this may be a
dumb question, but that's never stopped me before. :) Could the feed
be rerouted to an external resevoir and electric pump? That would
solve both the carbon buildup and tiny chain problem. Possible?
Impossible? Not worth the effort?
Glenn
houlster
In article <326C53...@worldnet.att.net> Paul Lamar (paul-l...@worldnet.att.net) wrote:
> I think the Mazda is worth trying in an aircraft because it is so
> simple, light weight and robust. No exhaust valves to burn for an
> example. The remaining problem is a poor 0.52 BSFC. I would like to see
> someone try a blow down turbine made from the hot half of a turbo
> charger to solve that problem. My plate is full.
What? What's a blow down turbine and how would it help the BSFC? Is
this something that has been tried before?
>
> BTW you don't need exotic steel in the exhaust if you segment it.
What do you mean 'segment'? Do you mean several short pieces lined
up together?
--Dan
Charles K. Scott
In article <326B8B...@nt.com>
Glenn Scherer <Glenn_...@nt.com> writes:
> Corky, it's been 15 years since I had my 13B apart, so this may be a
> dumb question, but that's never stopped me before. :) Could the feed
> be rerouted to an external resevoir and electric pump? That would
> solve both the carbon buildup and tiny chain problem. Possible?
> Impossible? Not worth the effort?
>
> Glenn
Don't see why not but it's just one more detail to work out for safe,
reliable operation.. That was the original plan Mazda thought about
but, as I mentioned, they decide that Joe/Jane customer wouldn't
remember to refill the reservoir and would then have dead engine. But
for me it was just the last straw of a number of things I didn't want
to deal with. The extreme exhaust heat was another and the high fuel
burn figured too, as did the need for a stainless steel muffler.
That's just me though, others aren't bothered by these problems or
should I say features? And there are a number of them flying.
Corky Scott
Thomas A Suit
Charles K. Scott (Charles...@dartmouth.edu) wrote:
: In article <326B8B...@nt.com>
: Glenn Scherer <Glenn_...@nt.com> writes:
: Don't see why not but it's just one more detail to work out for safe,
: reliable operation.. That was the original plan Mazda thought about
: but, as I mentioned, they decide that Joe/Jane customer wouldn't
: remember to refill the reservoir and would then have dead engine. But
: for me it was just the last straw of a number of things I didn't want
: to deal with. The extreme exhaust heat was another and the high fuel
: burn figured too, as did the need for a stainless steel muffler.
How bad is the fuel consumption?
-Tom
Jonathan Erlank
Paul Lamar wrote:
> the center housing. It then becomes what is known as a peripheral(sp?)
> port. It is a little more complicated then a simple two cycle port job.
> You also need to do a little grinding in the water passeges around the
> spark plug area and use long intake runners.
Paul, awhile ago you seemed against these engines seems now your an expert. However a
peripheral port is not simply a matter of port enlarging. I suggest If you havent
built a few not to advise anyone else as disappointment will be enevitable. There is
far more to a two hundred hp rotary than port shape. How do I know? I have a 212hp
turboed version and a 180 hp normal aspirated engine. It took years of acquired know
how to get them reliable.
>
> Mazda did not do this on the street engines because it ruined the low
> RPM torque which you don't need in an aircraft engine.
>
> There was a one rotor running at Copperstate on a test stand with a
> muffler that was very quiet. Prop noise is so high that a muffler on an
> airplane makes less of a difference than one would at first think.
>
> The definitive book on the rotary is simply called "ROTARY ENGINE"
> by Kenichi Yamamoto published by Toyo Kogyo Co. Ltd. (Mazda) in
> 1969. This is a highly technical book chronicling the development of
> the wankel by Mazda. Kenichi is an engineer and has risen to be CEO of
> Mazda.
>
> Another technical book on the Wankle rotary engine is; "The Wankel
> RC Engine Design and Performance" by R.F.Ansdale Published by A.S.
> Barnes & Company Lib of Cong 69-18692
>
> Paul Lamar
Charles K. Scott
In article <326C53...@worldnet.att.net>
Paul Lamar <paul-l...@worldnet.att.net> writes:
> What if your cam cog belt breaks? What if your three wide, cam cog belt
> PSRU cog belt breaks?
>
> If you don't think the stock Mazda oil injection pump is up to it.. I
> do BTW.... it is no big deal to build your own positve displacement oil
> injection pump.
You don't sound like someone who should be flying; too many things to
go wrong. I was wasn't talking about the reduction unit but since you
brought it up, Lou Ross makes a planetary gear reduction unit, not a
cog belt type (although they make a cog belt type too). Once again, I
must ask you to cite your failure statistics. These belts are designed
to last over 800 hours in high torque/high power usage, replacing them
every couple of years, depending on your flight time, would more than
suffice.
You say: "it is no big deal to build your own positve displacement oil
injection pump" Then do it and do everyone who wants to use this
engine a BIG favor while accomplishing something positive for a change.
As you've said yourself, "when the flag drops, the bullshit stops."
You say your plate is full? No one elses is?
Corky Scott
David Munday
In article <3269FB...@mail.idt.net>, Tony P <ae...@mail.idt.net> writes:
> I have a question about that "180 HP." Figures I've seen seem to
> show that only the highly-modified, expensive rotaries are producing
> that, and the more low-key ones are producing comparable to a 160 HP Lyc
> O-320.
Tracy Crook is making 160 Hp with intake tuning that is highly sub-optimal. In
fact it's about the worst intake tuning you could imagine. The rotary has been
shown (by mazda I think) to be quite sensitive to intake and exhaust tuning.
The assumption is that the thing will make 180 Hp with tuned intake runners,
and still running at stock RPM.
I plan to add mild boost to reach 200 Hp. You can also spin the thing faster.
The Hp to RPM curve is fairly linear, and there is little in the engine that
will complain at faster RPM. Those who blow them and spin them fast reach 500
Hp and still get enough life out of them to last a racing season without
teardown.
--
Dave Munday - mund...@miavx1.acs.muohio.edu
Web Page: http://ourworld.compuserve.com:80/homepages/munday
PP-ASEL - Tandem Flybaby Builder - EAA-284 (Waynesville, OH)
Say whatever it is you have to say; Say it clearly; Say it ONCE.
Charles K. Scott
In article <54o8lr$6...@portal.gmu.edu>
ts...@osf1.gmu.edu (Thomas A Suit) writes:
> How bad is the fuel consumption?
>
> -Tom
Tracy Crook has actually managed to bring his rotory powered RV-4 fuel
burn down to within a few points of a typical piston engine but he runs
his at extremely low power settings and is happy with what other RV
owners consider a low cruise speed. All things are relative and Tracy
is used to flying around pretty slowly. Cruising at 150 mph for him is
really ripping along. Other RV drivers are more used to cruises that
can be as high as 180 or 190 mph.
It isn't that the Rotory engine has an atrocious fuel burn but it's
always worse than a piston engine of similar power. I wanted to
squeeze the maximum efficiency out of my engine so I decided the rotory
wasn't the best choice for me. But that's just me. Paul is partial to
them and doesn't mind the slightly higher burn... in theory :-) he of
course doesn't actually have a homebuilt or a rotory engine.
Corky Scott
Charles K. Scott
In article <327571...@worldnet.att.net>
Paul Lamar <paul-l...@worldnet.att.net> writes:
> Corky owns a Buick block and heads but no real crank or rods let alone
> the rest of the engine as far as I know :).
>
> Paul Lamar
Wrong again and I might add, as usual. I have the crankshaft it's from
a Buick 300 cid V-8 which, when used in the 215 strokes it to 266 cid.
It's been inspected, magnafluxed and nitrided by the good folks at
Moldex Tool Co. in Dearborn Heights Michigan. Moldex does everything
to cranks from machining them out of raw billets to inspection and
polishing. They can and have made cranks for just about every engine
ever produced. They are a small company and do such quality work that
they are crazy busy all the time, it's almost impossible to get stuff
from them quickly but the wait is worth it.
Like many builders, I don't have a lot of money to throw at the
project. Right now I have college tuition bills to pay for the kids so
I just can't go around buying items like a $1,500 fuel injection unit
or $800 ignition modules so I may have to wait a while on them. But I
haven't even started on the fuselage yet so there's no rush.
Charles K. Scott wrote:
> Paul is partial to
> them and doesn't mind the slightly higher burn... in theory :-) he of
> course doesn't actually have a homebuilt or a rotory engine.
Paul replied:
> Not true! I currently own two. A 1976 Mazda Cosmo and a 1985 RX7 among
> other cars (4 cars total right now and a 182). I have owned a 1972 RX2
> and a 1975 RX4 station wagon.
This group is rec.aviation.homebuilt and I was referring to engines
used in aircraft.
Corky Scott