Konrad

Size?
Then wouldn't the Super Tiger muffler reign supreme?
Size is not the primary issue but rather that the muffler design can utilize the exhaust flow and thermal characteristics to scavenge and supercharge the cylinder.


All the best,

Konrad

Kweasel

My Feedback: (29)

The Tower muffler is a mini pipe.

Konrad

Not sure that term is well defined. I have seen extractors called mini pipes. It is a tuned exhaust system that does supercharge the cylinder at resonance. I know it as a 1/4 wave pipe/muffler. Maybe the moderators can give us a link to its operation.

All the best,

Konrad

longdan

For an untuned bolt on muffler, yeah, its the size of it that counts. Its not a tuned pipe, just a big muffler, but due to its size, it does show some characteristics similar to a tuned pipe.

The tower muffler is a bolt on performance item for a standard engine.

blw

My Feedback: (3)

It is very popular because of it being a simple bolt on muffler that will probably give a 40-46 sized engine a good boost in power. It seems that an 800-1000 rpm gain is the average. It is also popular because of the great price.

Konrad- I'm surprised you don't know about this muffler. Here is a link to learn about it: http://www3.towerhobbies.com/cgi-bin...?&I=LXJB16&P=7

Konrad

I prefer the designs from Jett Engineering and those formally sold by Performace Specialtiest
http://www.jettengineering.com/accy/accy.html
http://www.pspec.com/

All the best,

Konrad

spaceworm

The price of the Tower is $14.99. the price of the Jett is $60.00. What price performance?

Regards, Richard

_Tommy D

My Feedback: (20)

The Tower Muffler (along with the engines) are on intergalactic back-order. Your not likely to ever get one from Tower again. Last Ultra Thrust Muffler I bought I got off E-Bay. Again looking like they have gone by the wayside.

Jett However will be happy to sell you a muffler.

Tommy

w8ye

My Feedback: (16)

I had three Tower 46 engines at one time that now belong to Cliff Betton and he says he has worn them out over the years.

The one I used for over 100 flights had only a Tower Power plug which compare with the OS A3 which is a hot plug so I cannot share any comparisons of different plugs in the Tower 46.

My Tower "tuned canister" muffler caused problems on the engine. When the engine revved to the tuned area of the muffler, it would go leaner than the rpm's below the muffler tuned region. To set the needle correctly for full throttle would leave with a very rich mid range.

My muffler fell apart and the back end fell into a sewage lagoon. As has been mentioned, Tower was out of stock for the back piece of the muffler or even the muffler itself. But they did have Tower 46 engines. So I bought some more Tower engines to use the muffler from one. Later I was able to get the part to repair the first muffler.

While I was waiting for a muffler, I used a Mac's One Piece black muffler on the engine. I had to screw the high speed needle "in" to compensate for the increased muffler pressure to the tank. Now the engine ran very well. No rich mid range like with the Tower muffler. But I lost all that magnificent power that the Tower 46 had originally. Now it was just a regular 46.

I never used a muffler from the the other Tower engines I had.

Eventually, I repaired the original Tower 46 muffler and placed it back on my Tower 46 engine. The fantastic full rpm power and the rich mid range returned also.

Konrad

Only you can make that determination. But as a wise man once said the only thing better than cubic inches are cubic dollars.
But I agree for the sport pilot the TH is/or was more appropriate.

The point that needs to be said is that the reason there was 1.1K difference in RPM as because the TH muffler/pipe design supercharges the cylinder. The OS "box" is just a baffled expansion chamber design.

The OP was happy with the tractability with the OS but was concerned with the loss of rpm. He was not happy with the tractability with the TH muffler and was wondering why the huge change in mixture setting and if a different glow plug would help. I tried to explain why the mixture needles need to be changed and how and where the glow plug information can be used and found. I was reluctant to go into specific issues with the muffler type until the OP asked. I tried to lead the conversation towards that direction.

All the best,

Konrad

blw

My Feedback: (3)

I've had my TH muffler on both an Evolution .45 and .46NT. I didn't fly the .45 enough to comment, but it gives the 46 a lot of extra power. I don't think there are any rich ranges. I wouldn't put the Evo muffler back on the 46. I'm also using the OS A3 plug.

jaka

Hi!
Let me set things straight!

A "hot plug" is a plug that fires the fuel mixture early.
A "cold plug" is a plug that fires the fuel mixture later.
It's that easy!

But!
To get the most power from our engines we have to use the right fuel/glow plug/prop/head clearence.

Four variables that makes all the difference!

So more pressure from the silencer has nothing to do with more (or less) power!

More power from our glow engines is gotten from:

Either using more nitro in the fuel and at the same time retard the ignition point by using a colder plug, and eventually lowering the compression by adding a head shim!

Or...by using less nitro and rising the compression by removing one of the head shims....and using colder plug.

Quikturn

My Feedback: (12)

That's interesting to know.

I have mostly used OS #8 glow plugs with good results on all my engines ranging from 25's thru 61's. But I was wondering, should I use a hotter plug in the winter or stick with the #8 plug?

w8ye

My Feedback: (16)

Most people just stay with the OS #8 but it sometimes depends on the engine you are using

Konrad

Thats a sad comment on the state of affairs at the field.

While the #8 often works fine, it might be the easiest to find but not the most suitable. As engine enthusiasts and sport pilots alike I would think trying to get the most performance from one's engine would be desirable. Performance being power and/or reliability. Selecting the proper glow plug should be part of one's set up routine just like finding the proper prop for your plane and engine combination. It looks like we have a lot of work ahead of us trying to show how this is done. It is easy and I think the chart listed earlier give adequate information in selection the proper glow plug.

All the best,

Konrad

earlwb

When I wanted the most performance out of my engines, for example, pylon racing. I would pull out a nice collection of assorted glow plugs and try each one and see which one worked the best. every extra rpm counted.
But nowadays, I am just sport flying, a extra 50 or 100 rpms or maybe 200 to 400 extra rpms means little. So why bother with it, unless you have a good reason to. Nowadays I don't fly WOT much so the extra performance doesn't gain me anything.

Of course I am seriously considering the new Hangar 9 Jackal, so maybe I'll have to break out my collection of glow plugs again. Who knows.

Konrad

I have found that with regard to the glow plug, power and reliability go hand in hand, Besides why not get the most for your money (or weight) and set up the engine as well as possible?

We are talking a lot more than just a tach race.

All the best,

spaceworm

You appear to be very knowledgable on a wide scope of engine theory and issues. What is your current or recent past experience with gas, Diesel or glow RC engines,? Are you available for private contract consultation? Thank you very much.

Sincerely, Richard

Konrad

Thanks for the compliments.

Now define Current and Recent .

PM me.

All the best,

Konrad