DA85 on pipe! Results please.

[STLAV8R]

	Quote: Originally Posted by Ground Pounder
	Finished my EF 110 and got a few flights on it. The DA 85 with a 1090 turned 5650 using a Xoar 28 x 10. This was at sea level and about 60 degrees. Pretty poor results. The 85 already had 5 gallons through it using a Pitts. Called DA and talked to Tony. I had a Mej 28 x 10 in stock so I decided to give it a try. Temp was 52 degrees. The 85 turned 6575. Bottom line is the Mej sure makes this engine rip. Linear mid range and plenty of power.

Wonder what it would spin up on a 27x10 Mej?

[Henna_Ojisan]

On a Mej - 27x10TH my 85 was spinning around 6840. I'm at 6500 or so on a Mej 28x10 and it feels perfect. The 27x10TH spooled much faster and felt great for 3D - it ripped like crazy though... Same is true for the 28x10 over 2/3 throttle...

[sprice50]

	Quote: Originally Posted by Ground Pounder
	Finished my EF 110 and got a few flights on it. The DA 85 with a 1090 turned 5650 using a Xoar 28 x 10. This was at sea level and about 60 degrees. Pretty poor results. The 85 already had 5 gallons through it using a Pitts. Called DA and talked to Tony. I had a Mej 28 x 10 in stock so I decided to give it a try. Temp was 52 degrees. The 85 turned 6575. Bottom line is the Mej sure makes this engine rip. Linear mid range and plenty of power.

Did you actually try fly it with the Xoar? It would be interesting to see how it flies as ground testing can be deceiving. The prop obviously has a high load factor but may actually produce a lot of thrust in the air. Sounds like it needed another inch or 2 on the header with the 28x10 Xoar.

Funny thing is was going to try a 28x12 Xoar on mine, but this is obviously way to much prop. I might run it once and then cut it down to a 27x12.

I will still try my Xoar 28B (not sure how it will compare to the 28x10) but the airfoil is actually a lot thicker at the root than the 28x12 so I am not sure how it will compare.

Oh well, mine is an experiment in quietening down the setup while retaining reasonable flight characteristics for one of the fields I fly at. I usually fly with a Mej 28x10 at a different field.

[Ground Pounder]

Yes I flew the Xoar. Even at 5650 on the ground the performance in the air was very good. The 110 was 29 lbs 5 oz.

However when I went to the Mej it was blistering. No comparison. The Mej is the magic prop. Great performance and a very linear mid range. When I talked to Tony he was very positive on the Mej.... and he was right (as usual).

[ejohn18]

wow 29.5 lbs and its blistering thats awesome im at 25.6 lbs on my H9 260 with that setup its stupid power. LOL

Eddy

[ejohn18]

I have a 24x12 mej 3 blade coming can't wait to try it. I also have the 85 on a stock muffler in a H9 Su26MM it awesome also just crazy at 23 lbs.

Eddy

[Ground Pounder]

	Quote: Originally Posted by ejohn18
	I have a 24x12 mej 3 blade coming can't wait to try it. I also have the 85 on a stock muffler in a H9 Su26MM it awesome also just crazy at 23 lbs. Eddy

No question about it. I had a 85 cc AW Yak that came in at 22 lbs.

I flew it with the 85 and a pitts and it was a blast. A bad battery pack caused an early departure to the great hanger in the sky after only 40 flights.

[ejohn18]

ouch!! I would not have thought a extreme flight would come in at 29 lbs that seems heavy to me.

Eddy

[Ground Pounder]

	Quote: Originally Posted by ejohn18
	ouch!! I would not have thought a extreme flight would come in at 29 lbs that seems heavy to me. Eddy

I agree. There is nothing extra in the 110". It is bare bones with 3 23000 mah A123s. Bottom line is that I got one with heavy balsa. I suspect that there can be a 2 1/2 lb swing on weight pending the type of balsa and how lucky you are in the lottery.

I expected 27.5 but even at 29.5 the slow flight 3D characteristics are clearly superior to any other comparable sized bird.

[ejohn18]

110" is a lot of wing if she floats like may SD YAK then you have a winner have had 2 of the extreme Flights and the quality is breathtaking.

My H9 Extra is on rails getting better every flight and very fast.

Eddy

[sprice50]

	Quote: Originally Posted by ejohn18
	110" is a lot of wing if she floats like may SD YAK then you have a winner have had 2 of the extreme Flights and the quality is breathtaking. My H9 Extra is on rails getting better every flight and very fast. Eddy

Good to hear. Post your rpm results here if possible. Also if you have a 26x12 or 27x10 Mej to compare the rpm results this would be great. It would give us direct RPM comparison to Reza's RE3 pipe thread.

[gene6029]

Where do the pipes come in as far as noise goes? Louder, quieter, or about the same as Cannisters or in cowl mufflers? I have an extra with in cowl muffler, loud as hell, and a cannister wont fit, but the thinner pipes look like a possibility. Its my backup plane for IMAC & would like to make an attempt at quieting it down some.....Gene

[ejohn18]

Mine has a unique sound like a motorcycle but I will see if someone can give me a DB reading this weekend. If they point it at the engine you will be fine


Eddy

[3D Joy]

Tuned pipes for gassers are typically as quiet as canisters. So it is very efficient at getting better power without more noise.

The problem is that with more power, the prop makes more noise since it turns faster so you have to better control the throttle. It is a bit harder to control throttle with pipes since the effect of the pipe is not quite linear. There is always some sort of jump somewhere in the powerband.

For those that think their setup don't have any jump, they are just not tuned.

What you don't want is to have the jump at the end of the power band, this is where you get a peaky response which is much more difficult to control and also much harder on the engine.

[ejohn18]

here is my first run on my DA-85 on a K&S 1090

Eddy