RE: Ebay DLE DA smoke muffler???
I'm familliar with these mufflers, they work great with smoke.
I built a Wild Hare sukhoi for a friend and fitted a DLE 111 with two of these smoke mufflers. They worked very well probably because the thin brass tubing is coiled up inside allowing the smoke fluid to be preheated before it is sprayed into the hot exhaust flow.
The only issue we had was noise. There are no baffles inside, and the exaust pipe outlet ends just at the weld, it does not go any further up inside the muffler to break up the exhaust gases before it exits ... so its almost like running the engine with open exhaust ports, this created a few 'polite' complaints of noise down at our field. Even tho' we rent the field, it is also part of a public park, so I decided to make some baffles, as the last thing we wanted was complaints from the public and to lose the field !
It's a simple enough solution, I cut two pieces of 22mm copper pipes long enough to slide up inside the exhaust outlet pipes and touch the top inside of the muffler chamber. I drilled out a series of 6mm holes [I think it was about twelve or so] all around the top 2inches of the pipe, then pushed them up inside the exhaust outlets all the way to the top inside of the muffler so the holes would be inside the muffler chamber to act as baffles and break up the exhaust gasses. Before I slid the last 2inches of pipe in I smeared it with some JB Weld epoxy to secure it and make a snug fit, then for added security I drilled and fitted a 3mm nut and bolt through both the outlet pipe and copper pipe about a 1/2 inch from the bottom rear ends. The results were amazing! A much quieter engine without any noticable loss of power, no more complaints, and impressive smoke!
As an after thought, if I was to do the mod again I would drill a series of holes all the way along the copper pipe which would make the whole thing lighter and put less weight/stress on the muffler outlet pipes, or better still use lightweight aluminium tubing. All I could find to fit at the time was some 22mm copper pipe which is a good fit.
The model has done around 10 flights so far with no problems and no signs of failing around the exhaust oulet welds.
Hope you find this useful.