There is no canister that will give the boost of a tuned pipe.

We sell a canister that is patterned from a KS for 26-30 cc engines, I've run it on the 20 and it gives a slight increase in top end and is very quiet. There a couple of problems with it though, the first is the header, it's made for the Zenoah 26cc and DLE30 exaust port but this is relatively easy to overcome and get it bolted up. The biggest issue is its physical size, there is almost no 1.20 size plane that it will fit inside of and any boost it provides is eaten up by the added weight.


http://www.valleyviewrc.com/Canister%20mufflers.htm

Jedijody - can you explain how a "tuned pipe" exhaust increases engine horsepower? I see they are long and narrow, which, from what little I understand about mufflers, seems like it would restrict exhaust, and so, allow less air\fuel mixture into the carb. Evidently I'm not correct. Also, would tuned pipes be beneficial to increasing power on any gas or nitro engines, or will some benefit more than others? And from the few I've seen online they're not inexpensive. Thanks.

I am in the process of assembling an Aeroworks Prox260 with a DLE 20 . Do you think the canister muffler
for the Zenoah 26/DLE30 will fit a profile model like the Prox260 ?

It is a nice cannister muffler, very good quality & good price as well. I find it is still overkill for the DLE20 though. But will measure the plane & see if it can work.

The AW ProX260 is small for a 1.20 to begin with, it's fuel tank sits where the header and canister would pass through.Will itjust bolt on as part of the assembly process...no... aresourceful modeler could do it if they didn't mind venturing away from the instructions a bit, putting the fuel tank onthe other side of the fuseand possibly modifying the header slightly.

Next time you run the engine hold your hand about 10-12 inches away from the exhaust outlet at a low RPM. You will feel littlepulses hitting your hand. These pulses are not exhaust gasses being forcefully ejected from the engine, they are sonic pulses from the rapid expansion of the burning fuel charge. A 2-cycle engine is by nature a very wasteful piece of machinery, On every revolution some of the fuel and air charge that is scavenged into the combustion chamber is spilled out through the exhaust port.

With these two things in mind picture a muffler (tuned pipe)that has reflecting cones inside that the sonic pulses you felt would bounce off of and head back toward the exhaust port, as the pulse reaches the exhaust port it shoves the spilled/wasted fuel and air charge back into the cylinder. This increases the density of combustible material in the combustion chamber making a bigger boom when the plug fires, bigger boom=more power. The tuned part has to do with the length of the header or more accurately the distance the reflecting cones are from the piston coupled with the volume of the pipe and how theexpansion of exhaustgases is controlled for an engine of a given size, that's why bigger engines need tohave bigger pipes. A tuned pipe can be tuned to a given engine for specific narrowRPM ranges and or specific loads or they can be tuned for very broad RPMand load ranges depending on length, reflector shape, size, distance from the piston face, and volume of the pipe. The outlet of the pipe plays a minor role but is always smaller than a side dump soup can muffler because by the time the exhaust gasses get there they have cooled and begun to shrink so a smaller opening is adequate to let the gasses out.

This isa simplified explanation, from there it starts getting very technical and its discussion could fill an entire forum on its own, search the web and you'll see what I mean.

Jedijody - thanks for the detailed explanation. It's more complicated than I thought. And I will do some more reading - actually sounds
like some pretty precise engineering involved - cool. And that graphic helps, too.

The AW PROX260FREESTYLE comes in two sizes, the .90 is what I have my DLE20 on.
If you're looking for more power via a can or pipe, absolutely no need.
At 7lbs with this DLE20 swinging a Vess -or- Zoar 17" prop, you'll be getting over 14# thrust!
With such large wing area for a .90 size profile, and large control surfaces, this is a great combo for a DLE20,
as profiles go.

If, however you're in need of something less loud due to noise constraints where you fly, you might consider
this (it's a DIY compromise)(page 2);
http://preview.tinyurl.com/4qytcsc
Richard used a header pipe + a beer can

You can catch up with Richard over here;
http://preview.tinyurl.com/49o7jw5

I haven't (yet) gone that direction. But check out those web sites and see if what he's done, might be up your alley.

My next project is an SDS Yak Pro from VVRC, DLE 20, Macs 2986 Header and an ES Composites tuned pipe. Excessive? You bet! I like spirited aerobatics but am not into 3D flying (specifically hovering) but I do want it to do as much crazy crap as I can think up. I'm hoping this combo will turn a Vess 18x6 in the mid to upper 8K range. 15lb+ of thrust should git-r-dun!

The price on that composite pipe is a weee bit hard to swallow though.[sm=greedy.gif]

As to the thrust you'll get......might want o watch out for the MiB when they come
a knockin on your door, after your DLE20 reaches the stratosphere![sm=shades_smile.gif]

The Macs Quiet Pipe for the DLE 20 is $12 less at more than double the weight though. Besides I've been eyeballing ES Composites' pipes since I found their site a couple of years ago. I just gotta have one!

Went to my local hobby shop at lunch today and they have a used SD Yak Pro hanging up. Covering still looks pretty good and it has four HS-645s in it. I'm not a huge fan of that servo because they are so slow but the price is right and I may go pick it up tomorrow.

Gorgeous work and ambitious goal. Keep us posted with your progress.

"might want o watch out for the MiB when they come
a knockin on your door, after your DLE20 reaches the stratosphere!"

Much less the FAA...but seems that they are going to get into our face anyway. Sure hope not!!!

Need some input:

I have been flying RC for quite a few years, but only glow powered in the .40-.90 size range.  I am interested in trying a gas engine.  The new DLE 20cc sounds like a good place to start.  I'd appreciate any comments you might like to share if you have one of these engines.  for example, will this engine fit most .90 size planes or would it be a better fit with the 1.20 size planes? 

Many thanks,

Start reading the forum.....a great deal of information is posted...you will learn from other people's mistakes...
The forum is very interesting...not all of it will apply now...but down the road it will prove very valuable..

Codimasta
AMA 11269

60-90 size for crazy power, 120 size for "normal" flying.

Scooterinvegas

I really like a concise answer!  I get the point and prefer "normal" flying.

You might find my 'guide' of some help in deciding;
http://www.rcuniverse.com/forum/fb.asp?m=10197929

Jonde,Welcome to the DLE-20 forum! The DLE-20 and/or the DLE-30 are both good engines that many people have had great success with. I have been following this forum for quite some time, and I agree that reading the collective history of this forum is a good suggestion. There is a great deal of wisdom buried in these pages. The place to start is with post #1 which has been designated as the "summary" post for the DLE-20. Comments in post#1 include what size planes are good fits for the DLE-20. For example, here is an excerpt from that first post:

So the short answer to your question is that the DLE-20 will probably work in most .90 to 1.20 size planes. The specifics of the plane (weight, wing loading, etc.) and your flying style (acrobatic, scale, 3D, etc) will also be a consideration. So the long answer is that there is no short answer (;&gt. Post your questions here, read back in the previous posts when you can, use the forum search function (before you post a question, if possible) and we'll work it out together. Enjoy.-Mike

It doesn't necessarily have to be a .90 size and up plane. For instance I put this engine into a 60 size edge 540. A lot of people are putting this into a 60 size plane, but you may find that there is not alot of room to work with.

Biggest problem with that theory is that such models are very lacking in the total wing area.
Such models generally aren't as stable so equipped as they were originally designed to be with the correct engine.

It's doable, just not a very good idea.

Which pitts exhausts fit the DLE 20 ?...Rcgf ?..
Thanks

Jtec

Litterbug

I agree with you that a .60 size model could work, but I am spending too much time  already trying to pack an engine/fuel tank in to a too small .46 or .60 size plane.  Then, as I'm sure you have experienced, you often end up having to add weight to the tail to compensate for the added engine weight.  If I go gas with either the DLE 20cc or JBA 15 I am thinking I will go up in plane size as while.  Besides, as I get older I kind of enjoy the models with a wingspan of about 72 inches. 

I do appreciate your thinking of the options available however.  I have never owned a gasser, but I have noted the dimensions on these gas engines.  Looks like you need about another 1.5" or so for the rear mounted carburetor on the DLE 20cc.  I guess you could do a cut out in the fire wall. 

Thanks for the input.  Food for thought.

Mschulz531

Thanks for the practical advice.  I guess I got the cart in front of the horse.  I just started with this web site and forum so I just kind of jumpted in.  I have taken your advice.  Reading the collective history of this forum first makes a lot of sense.  I will try to reserve my questions to the, as yet, unanswered or unresolved specific issues. 


Thanks again,