DA 170 gas engine forum/thread

[orthobird]

i just checked my telemetry from todays flights and the idle was 1600, granted, i am using the white rose disc brakes, and maybe i could idle it down more. at 1600 rpm, minimal shaking.

 

[orthobird]

date: 8/23/2014

Engine: DA 170 twin with MTW RE3 pipes X 2

Fuel / oil mix: 40 to 1 red line, 93 octane, ethanol free

altitude: 260 feet

ambient temperature: 98 f

prop size: 3 blade mejzlik 28.5 x 12S

air frame: 3dHS Extra 330 LX 120"

radio system: Jeti



data:

1. high temp during flight (not after landing): 281 (right cylinder), left cylinder 251 F

2. temp range right =219 - 251 F, left cylinder = 256.1 - 281 F

3. rpm range 1600 - 6750

4. rpm max during flight 6750

5. rpm max on the ground= 6300

6. Rx voltage = 7.40 at start of flight, and 7.36 at end of flight (lipo batteries 2s, x2 batteries, 4400 mah each battery)

7. Rx voltage minimum during flight = 7.11

 

[parapup]

What are your thoughts on the white rose mains with brakes? I need a new set of wheels and was going to go with the 5" wheels but never thought about the brakes. Are the brakes worth the money?

 

[Phil.Griffin]

May I ask an (almost) totally unrelated question about the DA-170?

At some point, I plan to assemble a Pilot 37.5% Yak. My previous SD Models 37.5 had a DA-150, and performed ok. I'd like to put a DA-170 on my next one, but some time back was hearing of some transition issues with this particular engine. One friend of mine was so frustrated with his that he bought a 3W 170 instead. My question is, has anyone here heard of this issue. Was it real and widespread and has it been remedied ?



Thanks...

 

[orthobird]

today was my first time using the brakes on asphalt, and i was quite impressed. 1st of all, when you are ready to taxi, you can have your assistant let go of the airplane, and it just stays there, once you give it some gas, it starts to roll, the moment you lower the throttle, then it stops again. take offs are the same as before, meaning, once you give it gas to take off, you cannot tell the brakes are on. now, the most impressive part is landing. it was AWESOME!!! the moment i landed, it soon came to a stop within 20 to 30 feet i would say. again, you have the option to select the amount of tension on the disc brakes. i am happy with them.. they are on 5" wheels/.

 

[orthobird]

Phil Griffin;10173 wrote: May I ask an (almost) totally unrelated question about the DA-170?

At some point, I plan to assemble a Pilot 37.5% Yak. My previous SD Models 37.5 had a DA-150, and performed ok. I'd like to put a DA-170 on my next one, but some time back was hearing of some transition issues with this particular engine. One friend of mine was so frustrated with his that he bought a 3W 170 instead. My question is, has anyone here heard of this issue. Was it real and widespread and has it been remedied ?



Thanks...

Hi phil.



yes, this has been remedied.



i have 2 170's.



the first 170 i bought from a guy who won the engine at a contest. Now, the engine i obtained over 2 years ago. and i do not know how long he had that engine. it was packaged brand new and he never opened it or used it. BRAND new engine. well, that engine gave me a lot of problems, and recently, i sent it in to DA and it has returned, and now it is a totally different motor. this is the motor that i am reporting the telemetry stats on for today. it is in a 3DHS extra 300 LX. i have competed in one IMAC event with this motor, and including the practice one week before the competition, the airplane had a total of 28 flights and 56 sequences completed, without a single issue.



ok, my 2nd DA 170!!! this i bought brand new from DA about 1 and 1/2 years ago. this motor is in a BH yak 40% scale airplane. i did my 1st IMAC competition with it, and have flown this airplane in multiple fly in events. it probably has over 80 flights on it. this motor has stock DA muffs. i have never, i mean, never, even touched the needles on this one. it runs great each time. has never had a deadstick.



if i were you, i would go with a DA 170. or, DA 150 with MTW RE3 pipes for IMAC. if you want 3D stuff, get the 170 with stock muffs or cans(you could lose power with this), and you will be good!!!

 

[Phil.Griffin]

Thanks. 3D is my only thing at the moment. As such, I'm looking for smooooth transition. In-cowl mufflers are where I seem to find the transition I need. Do you know what DA did to remedy the transition issues?

 

[orthobird]

it was something with the reeds and the timing. i think on the "other" web site, they have a thread on it.

 

[Super08]

It was a new reed block with a small hole drilled in it to resolve the fuel pooling issue that was causing the problem.

 

[Robotech]

Super08;10265 wrote: It was a new reed block with a small hole drilled in it to resolve the fuel pooling issue that was causing the problem.

And they nailed it. One small hole was all it took. It's amazing sometimes how little it really takes to solve a seemingly large problem.