Engine for 104" plane

[ericb]

I have a plane that I need to finish and am looking for advise on the power plant. It has a wingspan of 104" and length of 88". I think we have determined it is a Lanier Extra 300S designed by Godfrey. Here is what I was thinking.

DA 85 8.5HP 68oz
BME extreme 110 10.5HP 62oz
DLE 111 11.2HP 88oz


I really like the numbers on the BME, but I have not heard anything about how they run and last. I know the DA will be an excellent engine, but I am not sure if it would be enough power. I am having great luck with my DL 50, but I am not sure about the weight of the 111. I am leaning towards the BME right now. Any suggestions and experiences are greatly welcomed.

Eric

[3dAndrew]

Why not try a DA85 on a canister or pipe?

[BTerry]

Eric,

More information is required before any recommendations are formulated.

1) do you presently own any of these engines?
2) how much money do you want to spend?
3) how much room do you have for exhaust systems?
4) if the plane doesn't include a pipe tunnel, are you willing to go through the construction project? (it isn't really hard, but most people don't want to cut into a good airplane)
5) How much "ballast" do you need at the firewall? The BME is very light, the DA tuned pipe will shift mass aftward.
6) How stout is the engine box? Will vibrations from a single rip it apart or is it strong enough?

First thing I do is disregard ALL HP numbers and try to get an accurate RTF weight, and not just a bare-engine weight.

My BME 110 is beautiful, runs great, is a power monster, weighs ~84.5 oz RTF with mufflers and ignition (which is quite a bit less than the other two), but is known to be unforgiving of a lean run.

The DLE-111 is supposed to be an improvement over the DL-100, which was fairly good by itself. Very simple to operate and good power all around.

The DA-85 is a beautiful engine, runs like a beast unleashed, shakes a more than a twin, and really needs a pipe to make good power. On a pipe it will at least match or even beat the other two engines. On a pitts muffler it will be less powerful (but still sufficient).

The big difference will be on the spool-up where a twin TYPICALLY (not always!) smokes any single, especially a piped single. My experience with DA-100's and my BME makes me think of a YS 1.40 4-stroke engine vs. an OS 1.60 2-stroke nitro engine - the 2-stroke OS will really swing a big prop at high RPM but feels very soft around the mid range, while the YS feels much more solid through the midrange, and will accelerate any prop as fast as I can open the throttle (the OS takes 2-4 seconds).

Does this help?

[ericb]

	Quote: Originally Posted by BTerry
	Eric, More information is required before any recommendations are formulated. 1) do you presently own any of these engines? 2) how much money do you want to spend? 3) how much room do you have for exhaust systems? 4) if the plane doesn't include a pipe tunnel, are you willing to go through the construction project? (it isn't really hard, but most people don't want to cut into a good airplane) 5) How much "ballast" do you need at the firewall? The BME is very light, the DA tuned pipe will shift mass aftward. 6) How stout is the engine box? Will vibrations from a single rip it apart or is it strong enough? First thing I do is disregard ALL HP numbers and try to get an accurate RTF weight, and not just a bare-engine weight. My BME 110 is beautiful, runs great, is a power monster, weighs ~84.5 oz RTF with mufflers and ignition (which is quite a bit less than the other two), but is known to be unforgiving of a lean run. The DLE-111 is supposed to be an improvement over the DL-100, which was fairly good by itself. Very simple to operate and good power all around. The DA-85 is a beautiful engine, runs like a beast unleashed, shakes a more than a twin, and really needs a pipe to make good power. On a pipe it will at least match or even beat the other two engines. On a pitts muffler it will be less powerful (but still sufficient). The big difference will be on the spool-up where a twin TYPICALLY (not always!) smokes any single, especially a piped single. My experience with DA-100's and my BME makes me think of a YS 1.40 4-stroke engine vs. an OS 1.60 2-stroke nitro engine - the 2-stroke OS will really swing a big prop at high RPM but feels very soft around the mid range, while the YS feels much more solid through the midrange, and will accelerate any prop as fast as I can open the throttle (the OS takes 2-4 seconds). Does this help?

This does help. I will try to answer your questions as best I can.

1. No I do not own any of them.
2. I was hoping to keep it around $800. There are ads for the BME and DA right now in that price range, and I love the price of the DLE.
3. There is plenty of room for whatever I choose for exhaust.
4. There are holes for twin pipes in the fuse already. I got the plane "in the bones" and it still needs to be finished by me.
5. I am not yet sure of the weight placement yet as the plane will still need to be finished.
6. It appears to be well built and strong enough. I might replace the triangle stock with angled aluminum to be sure.

Other than being unforgiving of lean runs, how does the BME run through the midrange and idle. Did the DA85's get any smoother with the updates? I read somewhere that they did updates to help balance them.

Thanks for the help and keep it coming. Here is a link to the thread I started on the plane I have.

http://www.flyinggiants.com/forums/f...ier-maybe.html

[ericb]

Opinions on a ZDZ Super 80 with canister?

[Spdstr280Z]

	Quote: Originally Posted by ericb
	Opinions on a ZDZ Super 80 with canister?

I'm curious on this too... Especially at the price they are right now. As many good things as I have heard about the Super 80, or "J", and currently $150 less than the DA-85....

Jason

[carrid02]

just another angle to think about...

your 800.00ish dollars will hold it's value much better and longer with the DA... just a thought.

[carrid02]

oh... I do own a BME 110. I bought it with a plane RTF a few years back. I love the engine. It makes great power and has smooth transition. You do need to be very careful with overheating issues... it's costly to have one rebuilt.

Of your choices, I'd go with the DA because it holds value, runs great, and excellent service. All around good motor.

You might also think about gettng one of the first version DA 100's. It will do just about everything the 85 will, but it will do it smoother and the airframe will last longer.

[BTerry]

As I recall the KS tuned pipe for the DA is about the size of a softball bat. The total length of the pipe is about 30 inches and the header adds another 8-12" (can't remember exactly), and the pipe itself is 3" in diameter. I think the ES Composites pipe is narrower in diameter but is longer. It is quite possible these pipes are too long or too big in diameter.

Also a new DA85 + header + pipe costs just about the same as a new DA-100 (pipe and header cost about $350 or so). The 85 is a great engine but you do need to tune the pipe system for your prop to get the most out of it. Carrid's advice to look for a used DA100 is spot-on.

I have owned a few piped ZDZ80's and they run very well too. Dick Hanson has a piped ZDZ 80 RV-J (Super) and it is a serious monster, just about the most powerful engine in this size I have seen. It rips a 27" Mejzlik prop on uplines all the way out of sight at 4500' elevation. The ZDZ on sale is a very good deal. The DA85 is similar in power.

That said, I still prefer a twin. However this is a personal preference. I like them because they are very easy to set up and I feel I have better control in the mid range.

The DA engines will have a better resale value, but this is a hobby and not an investment! Look at it this way: Buy a new engine and run it for a year, then try to sell it later. All new prices included mufflers (KS 1090 pipe on the DA85), and used prices are typical resale prices: The new DA 85 will cost you around $1150 new, and you could probably sell it the following year for $850 - $900 used. The DA100 is $1350 with mufflers, and after a year of use could probably get $850 - $950. The BME 110 is out of production, but the 116 Xtreme is $1430, and used you can probably get around $900 - $1050 while the BME 110's seem to sell for around $800. The DLE-111 is $730 new, and probably can get $575 - $625 used.

The used DA will certainly sell faster than the used BME based on name recognition alone. HOWEVER!! If you start out with a used DA100 for around $800 or so, you are approaching the "price floor" for the engine where the price won't drop off very much. Say you buy the engine for $800, fly it for 3 years, then send it back for service to replace the rings and bearings and get "upgrades", you can probably sell it for $650 - $700. In good condition it will likely command a similar price indefinitely.

In terms of raw power, the BME is tops by several hundred RPM on MOST props with the benefit of being far lighter than the others (although it prefers a slightly smaller prop than the DA100 can spin). A piped DA85 is probably second, with the DA100 and DLE 111 jockeying for third (though they only fall behind at WFO throttle and have a strong advantage through the midrange over a piped single). Any of the engines mentioned in this thread will be plenty for your plane, depending on weight.

If the flying weight will turn out in the 20# - 25.5# range, one of the ~85cc singles (DA, ZDZ, 3W, MT, etc) on a pipe will be perfect. If the final weight will be in the 24# - 29# range you definitely want a ~100cc twin (DA, DLE, BME, 3W).

[ericb]

I just found a great deal on a DL100. I think this should do just fine in my plane. Thanks for all of the help.

Eric

[MODE 1]

Why no mention of a 3W 85.....Just wondering

[BTerry]

	Quote: Originally Posted by shyte
	Why no mention of a 3W 85.....Just wondering

I didn't reference the 3W only because he didn't specifically ask about it. The 3W 85 is a very good engine.

[ericb]

	Quote: Originally Posted by shyte
	Why no mention of a 3W 85.....Just wondering

The options I mentioned were ones that were currently for sale and in my price range.

[RTK]

One more thing to add about the BME 110. All the parts are available except for the cases, which Tom might still have a few. As long as you don't plant that engine into something really hard and break the case, bearings, cylinders, etc are all readily available. If you plant any engine hard into asphalt they will be a total lose anyway.

[ericb]

I found a DL 100 that is on its way. That should be a good match.