RE: Sundowner 50 Arf
 

Thanks for the images! Yes, indeed I checked the SD from Jett engineering, I even order the stuff needed based on that project :)
Which prop did you use for running the Jett .56 in, there was nothing mentioned about the .56 engine in the instructions that came with the motor?

RE: Sundowner 50 Arf
 

Got in 5 flights today!!! [8D]
I added 6oz of oil to my fuel - as Dub suggested.
I opened the needle 5 turns and fired it up. At full throttle it was turning around 16,000 with an APC 9-8. I ran it awhile to warm it up a little then peaked the motor to get a RPM number at peak (17,900), and immediately richened it back to 16,000. I shut it off and let it set for about 15 minutes. Dub said it should turn 18,000 with this prop, and he was right. I am probably going to run this motor 18,000+ at peak, and back it off a few hundred when it is broken in.
First flight was 2000+ off peak about 15,700.
Second flight was the same.
Third flight was at 16,200 still plenty rich.
Fourth flight was the same as third.
Fifth flight I leaned it down to 16,800. If the last flight - still rich - is any indication this thing is going to work good.
The bladder tank worked great. The motor didn't change at all, no matter what I did with it straight up - hard pylon turns - inverted!!
Here are some pics from today.

Here is where I put the fuel dot.
http://gallery.barrymorrison.com/alb...l_DSCF0184.JPG

Exhaust outlet I had to do a little work on this one. When I fired it up the pilot got smoked out!! The exhaust tip has somehow gotten inside the fuse. I lengthen it out a little so it can't go back in the fuse. Hits on the fuse when you push on it now.
http://gallery.barrymorrison.com/alb...l_DSCF0186.JPG

Here she sits on the tarmac after the fifth and final succesful flight.
http://gallery.barrymorrison.com/alb...l_DSCF0188.JPG

Loaded in my old wagon for the trip home. GREAT DAY
http://gallery.barrymorrison.com/alb...l_DSCF0190.JPG

RE: Sundowner 50 Arf
 

Ok I just picked up this plane with a 55AX, pitts muffler and JR DS-821's throughout and am looking for advice on props and how much speed I can expect. It only had 16 flights on it and was only $250 with all new stuff when built! Think I got a good deal! This is a replacement for my reactor that had an air speed and altitude disagreement! Just looking for your thoughts on this one.

Thanks Steiny

RE: Sundowner 50 Arf
 

Looks great! Glad to hear it is performing well !

RE: Sundowner 50 Arf
 

I got in a few flights yesterday the Jett is making some good power!
The last flight I set the motor 13 to 1400 off peak 16,600 to 16700 rpm with the 9-8 APC, so I haven't leaned on it yet.
On the last flight it took the Sundowner straight up - rolling - as far as you want to go.
I flew a few pylon laps and the thing turns great needs no tip weight. This is an impressive sport plane.
It will be interesting to see how it works when I run it hard and start playing with props.

RE: Sundowner 50 Arf
 

You guys build an impressive engine!!
Thanks

RE: Sundowner 50 Arf
 

Have fitted a OS95AX in my Sundowner with a Jett LX muffler spinning a 12x8 apc prop. Installation the same as the one on the Jett site. First 3 flights were dead sticks because of over heating, so i added more vents to the cowl and increased the size of the standard inlet holes. Then i went to a 20% nitro heli mix. Well this thing cuts thru the air like a hot knife thru butter, glides well, lands even better, and the speed is well awesome. It makes my Sports 40s with a Os55ax and a Mac look slow, and that pulls 100mph. I have a bushnell radar gun, and no one in my club has the guts to stand infront of it to get a speed reading...And i dont blame them!:D

RE: Sundowner 50 Arf
 

Hey Steiny,

I have the same setup, but I have not put the plane together yet, one of my projects on the back burner and the next one I am working on. Let me know if you get feedback or if you test fly it how it goes.

Chuck

RE: Sundowner 50 Arf
 

I CAN GET MY HANDS ON A JETT 90 L FOR A GOOD PRICE,THINKING OF REPLACING THE OS 91. ANY THOUGHTS ON THIS GUYS ?

RE: Sundowner 50 Arf
 

has anyone done saito fg 14/82 on sundowner 50? im planning to do it with my sundowner 50 any suggestion is welcome

thanks

RE: Sundowner 50 Arf
 

just buy the jett , you wont be sorry, and yah get to find out just how big a cajones the Jett has compared to the OS has[>:]

RE: Sundowner 50 Arf
 

DO YOU KNOW IF THE 90 WILL FIT WITH THE PIPE GOING THRU THE FUSE LIKE THE 60 JET DOES?

RE: Sundowner 50 Arf
 

I have the OS95AX installed with the stock muffler and am very disappointed with the performance. Can you post a pick showing how you fit the Jett muffler with the 95AX? I had some trouble getting a jetstream muffler with my O.S91FX in a former Sundowner 50. Did you use the Jett "llittel toni" extensions to divert the muffler away from fuse?

Thanks for the help

RE: Sundowner 50 Arf
 

No, the Jett 90 does not fit as well as the SJ50 or SJ-56LX

It is also not faster. just makes the plane heavier.

Given a choice, even an OS55 with the Jett muffler is a better setup than cramming a .91 engine in here

RE: Sundowner 50 Arf
 

YUP, NOW YOU GUYS ARE MAKING ME UNSURE :eek:

RE: Sundowner 50 Arf
 

Hey Bob, and everyone else,never posted here before but have a few questions if you have the time,

I used the same setup in the sundowner theBob has, with the jet stream muffler, and the exsaust exiting out the bottom. I havent flown it yet, but my question and concern is do you have a heating problem inside the fuselage. Meaning, does the heat from the muffler make it hot in side the fuslage. i was thinking about cutting out the spot at the bottom of the fuselage and the extra slot used for electric setup to create more airflow and less heat inside. I was wondering if this was a good idea and wanted to ask you what you have done before i cut into my plane? will the heat from hte muffler creat any problems inside, or does the radio equptment not get effected by the heat?
Thanks again,
Kristian

RE: Sundowner 50 Arf
 

Has anyone taken this airframe up to 175 mph yet? I checked a while back...but nothing. I do not plan on doing turns or maneuvers at that speed, at high speed I just fly it straight as I realize that you could break it in the air easily.

I have a 30cc gasser in mine with a 14x14 prop currently and am thinking of putting a carbon fiber tuned pipe on it for more speed...this will not change the weight of the plane by more than 1 or 2 oz. This combo makes over 4 hp...I guess its just a matter of propping it correctly. It seems right now I already need more pitch...I need a 14x16 as when I punch it...it instantly comes up to top speed...seems like it needs more load. Using time clocking over a known distance (600 ft), we're getting about 138 mph.

Although it is quite fast, I am a little disappointed I cant find a prop that is 14x16 or more pitch stock.
Anyone know at what point an over-square prop becomes inefficient?

The plane weighs 1 pound exactly over recommended flying weight and flies very well with no ballast weight added.

RE: Sundowner 50 Arf
 

a 30cc gasser in the SD50? Seems like it would be too heavy.

RE: Sundowner 50 Arf
 

To start with I find this one tough to believe! But, and I hate to say it, you may have to move into a 3 blade prop to get ground clearance.
I am surprised your ignition allows you to turn all of those RPM. Speaking of which, what kind of RPM are you getting?

RE: Sundowner 50 Arf
 

FYI the syssa engine in a sundowner is on youtube, and from the vid it turns 14k rpm, probably the best solution is for a custom laminated wood prop, like the unlimited scale racers use...FWIW

RE: Sundowner 50 Arf
 

Hi Morgan,
no i didnt use the extension, i mounted muffler exactly the same as Jetts 60LX. It went in no prob, but a little work was needed. You have to take out more firewall than the Jett 60 fitting, which doesnt leave much space between muff and fuse, about 2 millimeters is all. I will take some photos tonight and post them to show you.

Herbs

RE: Sundowner 50 Arf
 

I cut the bottom hole out of mine, and it works good. With the .56LX set rich it is a performer, and the fuse does not overheat. I have landed the plane after a fairly long flight, and immediately held my hands on the fuse top, bottom, sides, and it was cool to the touch. The end of the exhaust was hot enough to make you move your finger quickly!!! [>:]
To this point the muffler heat does not seem to be a problem. We will see how it works this summer when it gets hot.
Now if all this damn snow will melt!! We have been hit pretty hard *** my place is covered with about a foot of snow. If it warms up, it will still be another couple weeks before I can get in some more flights. [:@]
Earl

RE: Sundowner 50 Arf
 

Getting back to the 91FX, it weighs 5+ oz more than the 55ax, so if I put a big battery in the back to balance it, how does it do with a dead stick? I would think the wings are overloaded and it floats like a brick, is this right?

RE: Sundowner 50 Arf
 

With the .95AX, the battery is back as far as it would go in the fuse, and still had to put lead weights under tail to get correct COG. Its heavy, infact way to heavy, but it will glide with enough airspeed if you get a dead stick. If you are low and dead stick, well the ground will win.

RE: Sundowner 50 Arf
 

that makes since, seems like the weight would make it a brick, over loading the wing loading, what speed is gained by using your 95ax, is it a big increase?