Floyd, I like your thinking. That cone inside is a useless POS. I never had it do anything but overheat the engine and cause complication and believe me I tried to make it work. The outlet is too small and need to be opened as wide as possible as well.  Ken

That baffle is only good for the idle mode.  I pulled one out for an R/C pylon race.  It ran great, but would not idle at all.  Not needed for U/C except maybe scale events.

Paul

   I don't know how it works on this particular muffler. But the baffle is absolutely critical for the E2030 muffler on the 20/25FP and 25LA.

    Brett

Hi Brett,

The way the E2030 muffler works might just be one of those strange phenomenon that occurs every couple of millennium.  But it does work as advertised when used as part of the complete package!

BIG Bear
RNMM/AMM

Sure the weight is hard to beat but to me tongue mufflers are simply perforated strainers designed to spray oil and debris 180º.

Tongue mufflers are at best only good for reducing the bark of the engine and your right about the spray. But tube mufflers are just as offensive in their ability to make a mess. Rear exhaust and venting under the model seems to be the best solution,and electric is the hands down winner for clean sanitary running.

Tongue mufflers are at best only good for reducing the bark of the engine and your right about the spray. But tube mufflers are just as offensive in their ability to make a mess. Rear exhaust and venting under the model seems to be the best solution,and electric is the hands down winner for clean sanitary running.

Hey Dennis,
                    the thing I have against tongue mufflers is that they are not an exhaust system as such.
A 'system' directs waste gas, oil, heat and noise away from where it is not wanted and some systems require noise suppression and some don't.

Tongues dive straight into an attempt at noise suppression at the expense of all else and try and justify their existence on being light in weight.

But, yes I agree with the rearward exhaust mantra - every well designed vehicle follows suit and for a good reason.

Cheers.

HA!  Yes, a lot of powdered aluminum ended up on my workbench!   The Dremel sanding drum actually is pretty tough and cuts metal nicely.

Of course, the ultimate solution to exhaust goo is rear exhaust engine and a pipe or a long muffler.  I have several of those, but the OS46 spits out the side. 

I might someday be a fan of tongue mufflers, but they are all too short!  Hey, a longer one would get the goo away, but they are just short enough to spread oil all over!

FLOYD

Slimline mufflers had the right idea about length when they made their tongue mufflers. But the rest of it wasn't up to standards of efficiency

Practically speaking if there was an efficient muffler for c/L no one would use it simply because of size and weight. Aluminum is not a real good dampening material for noise, the choice for most is light steel and sufficient volume to slow everything down before it exits the stinger.
Bob Davis at Davis Model Products supplied some of the most efficient German made mufflers to the r/c community and had very little luck with them because of the same objections as the C/L crowd. That said Europeans fly large gas burning models with no more noise then the family sedan because they have to comply with strict noise restrictions. most have very well designed steel mufflers with efficient baffles in them. Regretably efficiency is probably not pretty on a stunt model.
What would I judge as efficient. When you can fly in a populated area and not be chased  because your a noise nuisance.

I think that pure exhaust noise is somewhat overshadowed by prop noise and this muddies the waters in regards to what is heard as an 'efficient' muffler.

I have seen straight through all aluminium mufflers that work on the absorption principle wrapped with glass matting that are very good at noise suppression - the only down side is having to repack them from time to time . If you want a really quiet and simple system then extend a perforated pipe from your exhaust, wrap it in fine glass cloth and slide a covering tube over that - no need to seal off the ends of the outside tube if it is a good tight fit.
Light, easy to make and has very little back pressure, but as I said you will have to repack it every now and then due the weight gain from oil absorption.

The Davis muffler, was that the reverse flow three piece cast job that emulated the BMW motorcycle design? Totally over engineered in my opinion if it is what I am thinking of!

No matter how quiet your model ends up, if you fly control line in continuous cyclic circles there will always be the repeated Doppler effect that will drive people nuts. The human mind simply hates the same noise rising and falling over and over again (this effect is the basis of most alarm systems) no matter how low the Db reading is.

The Davis muffler, was that the reverse flow three piece cast job that emulated the BMW motorcycle design? Totally over engineered in my opinion if it is what I am thinking of!


None of the Davis mufflers were cast.

Dennis

Hmm, must have been one called the "Snuffler" then.

Thanks.