So what's the difference between things like the Bisson, Slimline 'Q', JTEC, etc.

I've got a 120AX that needs a scale-like muffler and I know nothing about them. Will probably be mounted on it's side - 90*

Any feedback is great. Thanks!

The last time that I checked or paid attention, the Bisson Pitts mufflers (side mounted engine, straight down dump) were considered the best of the choices you listed. That was several years ago. I doubt that anything has changed significantly since then.

I have Bisson Pitts mufflers for my Thunder Tiger 1.20, Super Tigre 1.40 (G2300) and my OS 1.60FX's. All work flawlessly with no failures or problems, such as poor muffler pressure force.


Ed Cregger

You might want to take a look at what these guys have to offer:

http://www.mecoa.com/tatone/mufflers/mufflers.htm

Good luck.
Bill

I have used bisson mufflers in the past but recently bought one of the "Q" series slimline mufflers, it looks every bit as good as the bisson with slightly more internal volume, and very light. This is worth taking a look at.

The tatone mufflers are a old type design IMO, cast from aluminum, heavy, low internal volume, loud.

http://www3.towerhobbies.com/cgi-bin...&I=LXUNU2&P=SM

Low internal volume causes the engine to over heat and detonate

Unless there has been a change the 1.20AX comes with a very nice mufller that can be mounted in the Sport or Pitts position and has the added benefit of a nice sound.

gaRCfield,

Take a look at the Turbo-Jett in cowl muffler. It is a tuned muffler made 'Pitts' style to fit in a cowl. The normally long 'header' is coiled inside the 'can' with the 'stinger' at the bottom. Very cool design that will boost rpm.

Also, I've seen pics of full scale planes in Switzerland that have an 'after muffler' showing on the belly looking much like our RC models with a TP or mousse can/canister type boosted exhaust system.

Terry in LP

Just use the stock muffler with this 90 degree adapter $27.99

http://www3.towerhobbies.com/cgi-bin...?&I=LXLPL4&P=Z

The 120AX comes with the 90* adapter. Even using this would require a giant cutout in my cowl with the muffler hanging out the bottom. Not the worst thing in the world, but I'd like to hide it if I could.


Sounds like the Bisson is good, the Slimline Q is good but don't see why it's 25% more expensive.

Thanks for the thoughts. Please keep them coming!

Who knows??

Is a OS .91FX really worth $100 more than a ST G-90?, tower hobbies seems to think so.

I wish I could understand the pricing of R/C items..............

Listening: consensus please?
So far, I have seen no real life data on which one is better. I am sure you, the American side exhaust gas dump users, can provide tons of information about:
1) noise
2) engine power (loss/gain)
3) weight
4) fitness for use (durability , tunability, etc)
5) price

We "American side exhaust gas dump users" are responding to fellow American gaRCfield's request for 'Any feedback is great. Thanks!'. Not doing lab work for you foreigners.

Terry in LP


This kind of language doesn't sound very cordial does it?

takin the easy way out eh?
How about some field experience?

edit:
we in Europe, furriners to you, are not allowed to run those noisy contraptions due to very strict noise regulations. In order to help you out, I depend on data you collect, and publish.
I hope you understand, that your field is next in line to be shut down if you care a hoot about your fellowmen.
This globe is getting more crowded every day. We need power to fly, and we need to do that as silently as we can, or others may object big time to what we do. They will probably outnumber us by a large ratio.
So let's share knowledge while we can and make the best of it.

Ok not trying to start any international wars here. I have never used anything other than a stock muffler on my AX engines. For my newest plane I'd like something that's a bit cleaner looking. I don't want a muffler that cost as much as my airframe, so options I've seen are the Bisson, Slimline, JTEC, etc. and am trying to decipher the differences between them. Also trying to figure out if I will lose or gain power, if I will gain better sound or make more noise, etc.

As far as Tower's pricing, I find comfort in using OS engines and think they are worth the extra money, so there may be some validity to Slimline costing more money. There may NOT be, too, which is why I'm here

Please keep the comments rolling in (and friendly!) as I know nothing about aftermarket mufflers and have no other place to go for questions and anwers.

Thank you.

Seems as though Bisson has been a little more progressive than Slimline in recent times. But this was not always the case.

Jtecs tend to be universal in nature with one size fits all type mufflers. I've not been impressed

J'Tec/Tatones date back to a time when almost all mufflers were designed to fit a range of engines. Even OS's #703 fit everything from the .30 up to the .58.

My family came from Scotland (and entered the port of Philadelphia in 1736). So, I guess I'm a far'ner, too.

David

Ok Bisson is starting to sound like the best option.

Last time I checked, anyone other than a native American came from the blood of a 'foreigner' at some point in time. My ancestors came here and worked hard to create a land of opportunity and freedom for all of us. And we're never going to solve the world's problems with the attitude of Americans vs the world, so I warmly welcome the thoughts of anyone, from ANY country or region.

Does one gain or lose power switching from stock to Pitts?

Also I've heard some people, well at least one or two, has had a problem with not getting enough tank pressure using the Bisson and 120AX. I'm thinking it was an isolated case or two though.

cool thinking
It,s nice to have roots.
I wish I could contribute more to this thread, but the only experience I have is with Bisson on an MVVS 25.4cc gas engine. Engine response was nice too.
Power was decent, A bit too noisy though, but the fit to the engine was quite close. If I had to choose for an in cowl muffler, it would be a Bisson for sure, because that is the one I know and would feel comfortable with.
dB production I estimated (well trained ears) to be about 85 dB(A) at 7 meters with an 18x8 prop at 7400 rpm. 5dB too loud for our field. (5dB is about 4 times the alowed noise!)

If you saw the pipes off on a Pitts you have ruined the muffler as far as muffler pressure goes. There is a rolled edge on the pipes

Will a pitts type muffler give me less power than the stock muffler?

They are about the same

Like PE said, we have no real data about the stock muffler VS a Bisson or Slimline. All we have are opinions with nothing to back them up. The question about the OS 120AX and the muffler choices has been asked before, more than once and no one is able to provide any data like RPM numbers or DB numbers. Of course it would require someone to test the engine with the different mufflers and several props with the same fuel on the same day and be able to take reliable measurements. This would require someone to spend considerable money on all the items, (engine, mufflers, props). Most individuals are not going to do this just for grins. Perhaps a magazine engine guru would do some testing along these lines but I doubt it. So we are back to where we started with interpreting individual opinions we read on these forums. Oh well.

Ok, thanks guys. One thing I just saw is the the new Slimline Q series is only 2.5 oz, opposed to the combined weight of 8oz for the stock muffler and adapter. It is my understanding that muffler volume equates to more power, but maybe almost a half pound of weight is worth losing a few rpm. The Bisson is just over 4oz, so if I'm going to pick one of the two, I'd go with weight savings since there is no cut and dry evidence that the Bisson is better.