DA85 on pipe! Results please.

[dbcaster]

That sounds good. I am not sure how the PAU compares to the Vess but the prop works very well. It is definately not quiet though. I had to send my 85 in due to the fact that the base gasket is leaking from all four sides already. This is my second 85 and my second one with the base gasket leak. I sure hope they figure it out soon because pulling the engines off after each gallon is a real pain.

[sprice50]

DB - strange about the base gasket. How bad a leak are we talking here? I don;t think mine has any issues.

[dbcaster]

Bad enough that I cannot even tune it. If yours isn't leaking, it sounds like you are one of the lucky ones so far.

[sprice50]

Yes, I have never had a problem. I'm glad about that! Haven't bothered with needles sine first run. Seems strange to me that a gasket would leak. What causes something like that?

[Henna_Ojisan]

I've been really lucky so far too - I do have a slight film but nothing that is affecting the tune.

My buddy has not been as fortunate and has sent his back to DA- seems it's not happening to all of them.

[dbcaster]

Here is thread with more info. http://www.flyinggiants.com/forums/f...-ooooooze.html
It has been said that only some of them are leaking. Unfortunately both of mine do.

[Henna_Ojisan]

Alright gents - as promised, I installed my Eagle Tree Logger and was able to grab some in flight data. I have the magnetic pickup sensor affixed to the ignition sensor and I'm using the hall sensor magnet as the source for my logger. I also have a thermistor between the 3rd and 4th fin on the cylinder head. I have the logger in line after my batt-share before the rcvr and servos. Works great for picking up mAH per flight as well as for tracking servo current draw.

I've got a couple graphs below and can display a wide array of data - let me know if you are interested in something and I'll see what I can do.

Summary of data:
** 88 Deg day, 40% Humidity, ~750' above sea level. Mixed IMAC and 3D.

- 6625 RPM on Mej 28x10 on ground
- 7246 RPM in flight (same prop - unloads ~600 RPM)
- Max CHT - 245 deg F. (extended hover and dropped to 190 once on the wing)
- Avg CHT - 175 deg F.
- Max current - 9.5 Amps (Servos - 6-5955's, 1-8711, 1-5965, 1-225MG)
- Avg current - 1.15 Amps

[3D-Seth]

I got the chance to run a DA 85 on a Grieve pipe (broken in), with a Mejzlik 27x10 on 89 octane gas @ 100:1 Amsoil. Tached it on the ground at 6440 RPM. Pretty ballistic if you ask me. It really shows in the air too.

Seth

[3D-Seth]

Great info Henna! Thanks for sharing!

[Henna_Ojisan]

No problem - I'll snap a couple photos of the sensors and mounts for those interested - works great and I have the dashboard in my canopy below my dash. It shows current pack voltage, RPM, Cumulative mAH, and CHT.

It's great to fire it up and be able to quickly see those readings without needing a tach, temp gun, etc...

[dbcaster]

Henna,
Do you have any baffling?

[Henna_Ojisan]

No baffling for the 85 - I do have the cowl cutout around the head and have good airflow over it. I've thought of a baffle to focus the air over the head but never did it.

I'm no expert on CHT - take a look at the below graph... From the reading I've done, an average CHT in the 150-190 range is ok, and an ocassional spike to the low/mid 200's is fine when 3Ding and after landing when you'll see heat soak. If I'm way off base - somebody please let me know...

I've not leaned the top end like I would on a stock exhaust or std. can setup as the tuned pipe setups will lean out on the topend a bit and it's better to run a tad rich.

On the graph below - here is what was happening:
- 0-0.6 - Starting engine
- 0.6-1.2 - Engine warmup
- 1.2-1.5 - Clearing out engine
- 1.5-2.0 - Low idle, taxi, and take-off
- 2.0-5.8 - IMAC style flying
- 5.8-6.8 - Rolling harriers
- 6.8-7.2 - Hovering
- 7.2-12.4 - IMAC style flying
- 12.4-13.0 - Approach/Landing
- 13.0-14.0 - Taxi, engine kill, wheel to pits (you start to see the heat soak)

[dbcaster]

o.k. good to know. I had baffling on mine for the first three flights. I had to make some engine mounting and thrust changes so I removed the baffling and opened up the cowl a bit on the last flight. I don't use a temp gauge but the temp after landing seemed good.

[sprice50]

	Quote: Originally Posted by Henna_Ojisan
	- 6625 RPM on Mej 28x10 on ground - 7246 RPM in flight (same prop - unloads ~600 RPM) - Max CHT - 245 deg F. (extended hover and dropped to 190 once on the wing) - Avg CHT - 175 deg F. - Max current - 9.5 Amps (Servos - 6-5955's, 1-8711, 1-5965, 1-225MG) - Avg current - 1.15 Amps

That's some awesome data!!! The eagle tree is great. So it seems the 1090 produces 185rpm more than the greeves on a 1" larger prop! Comes at the expense of a little added weight. Glad I went with the 1090 though.

Have you tried the 29x10 yet and will you be trying one?

[Henna_Ojisan]

I'm extremely happy with my 1090 too! Don't think I'll switch to a 29x10 as the 28x10 is perfect.

This last week I was able to fly my 50cc Extra with a DA-50, a 33% Extra on a Brison 5.4, a 42% Extra on DA150 and the power to weight on my 35% Extra is awesome!! Pullout and uplines seemed to be much better than the smaller birds and a tad better than the 42% (though that plane flies better than my 35%er).

I'm sending off my 85 for a replacement head gasket as the leak is getting a tad worse. Not bad, but I have a couple weeks of down time and it's a good opportunity to get it checked. I also checked both my needles and here at just over sea level I'm at 1-1/2 turns out on both the Low and High - pretty much stock settings...

Still loving it!