1QwkSport2.5r

After about 2 hours on the test stand doing a slow and steady break-in, I flogged several props to see what the little guy can do..
Air temp - 56° - a bit windy too.
Fuel: 5% nitro 20% castor homebrew
Plug: My usual McCoy MC59
Prop brand: All APC sport
Stock tiny muffler

These are all having the engine peaked just long enough to get a number then I let it run for 2 minutes 400rpm rich of peak.
9x5 - 13,560rpm
9x6 - 12,570rpm
9x7 - 11,670rpm
10x5 - 11,310rpm
10x6 - 11,110rpm

Compression isnt as high as I'd expect it to be, but it starts very nicely and throttles pretty well. Not the screamer I thought it would be, but it will do what I want it to do I think. I'm going to see if another muffler I have will fit and give it a little better performance.

1QwkSport2.5r

I made a bridge adapter for the muffler so I could hang a Thunder Tiger Pro .46 stock muffler on the little Enya. Quieter exhaust note, and more power.. what more could you ask for? More, of course!

About 50°F air temp, low humidity. 5-10mph wind.
Same MC59 plug and 2 washers from break-in, 5% nitro/20% castor fuel
All props APC.
9x5 = 2,600rpm/15,100rpm idle/peak (+1,540rpm)
9x6 = 2,500/14,040 (+1,470rpm)
9x7 = 2,600/12,900 (+1,230rpm)
10x5 = 2,500/12,600 (+1,290rpm)
10x6 = 2,600/11,800 (+700rpm)

I will test my .46 Jettstream muffler when I get another decent day without rain. I think this little Enya will give up a little more power yet.

buzzard bait

Very interesting...good job getting that much more with a muffler change!

I've had a number of the plain bearing ones and always thought the muffler was terrible. It's extremely loud, and now we know it's also very restrictive. I tried other mufflers for 36 types and got a little improvement, but nothing like this. Also, the Macs one piece type improved it a bit, and helped quite a lot with the noise.

I also appreciate that you went pretty high with the prop load. People don't realize you can prop these engines with quite a load. Power goes down, but the engine seems to handle them fine.

I've got some Enya 30 mufflers, and I'm thinking they might be good on my .19s!

I think Enya sells the 30 with a larger muffler now, if I'm not mistaken.

Thanks for posting.

Jim

1QwkSport2.5r

When I first got the engine and posted around the forum about it, the common response was Enya's like to scream, and the SS 30 muffler has a hefty bark to it. I'm not seeing the screaming part just yet, but the stock muffler is definitely loud. This engine is roughly 5-7 years old and I got it NIB. So far its only got 2.5 hours of break-in time on the bench and a tank of prop testing.

The 2 main variables that effect performance in regard to the muffler is shape of the chamber and the volume. Its a no brainer that more volume gives more power to a point, I was just curious to see what the difference would be and man was I surprised! I dont think I made a video of my prop testing, but I do have a few of the break-in videos on YouTube. The noise of this muffler is crazy loud. http://www.youtube.com/watch?v=Bb6p_mgXDpA

I have another muffler I am going to try thats bigger in volume yet (My .46 Jettstream) and see what gains or losses it carries with it. I will have more numbers when the weather gets warm enough to not gel castor oil.

Mr Cox

I don't have the SS30 myself but if it is the old-school lapped construction I don't think it is mean to rev very high. It is the more modern AAC constructions (usually denoted by CX, while the SS15 is an exception) that are revers while the lapped ones are old-school luggers with a strong bark...

The mufflers from Enya have increased in size and weight throught the years, so perhaps that is what you are seeing even more when going to a .46 muffler (larger volume and outlet area). Nice power increase though, how much extra weight did you get with the large muffler?

Mr Cox

I don't have the SS30 myself but if it is the old-school lapped construction I don't think it is meant to rev very high. It is the more modern AAC constructions (usually denoted by CX, while the SS15 is an exception) that are revers while the lapped ones are old-school luggers with a strong bark...

The mufflers from Enya have increased in size and weight throught the years, so perhaps that is what you are seeing even more when going to a .46 muffler (larger volume and outlet area). Nice power increase though, how much extra weight did you get with the large muffler?

1QwkSport2.5r

I know there isnt a lot of info out there about the Enya SS engines. There are some .25's that are stronger than the SS30 in stock form, but stick a bigger muffler on it and it really comes alive. It makes sense the lapped engines are a little barky. The stock muffler is way too small IMO.

I have the weight of the mufflers written down but I misplaced the sheet I wrote it on. I think the TT muffler is 2-3oz heavier but I'll have to double check.

I was impressed with the power gains, though it didn't gain nearly as much on the 10x6 as it did on the other props. Makes me think the 30 likes smaller props.

sarpet

new enya ss25al-chro https://cs206.xbit.jp/~w041133/store...roducts_id=438
jxf 9x5 prop
sm251 muffler
15%nitro
13600rpm peak.
and with os .25fx muffler 14300-14400rpm
enya muffler is very poor.

1QwkSport2.5r

Put a .46 size muffler on it and watch it come alive. On 5% nitro I got 15,100rpm using an APC 9x5 and TT .46 muffler on my SS30.

The stock Enya muffler is a power robber and it's loud.

airraptor

My Feedback: (66)

quick let me know what your next project is and i will see if i have a engine for you. I would like to do a engine up for you. i think i could get another 2,500-3000 out of that 30SS. the 35 AX will spin a 9x7 at 17,000 The cheap gp 42 can do 17,000 on the 9x8

1QwkSport2.5r

Tell you what... Send me one of your miracle engines to test out and I'll consider having one done.

The Enya is staying as it is. If anything it might get better exhaust timing but that's it. It's a lapped iron engine with a nitrided liner, not ABC. Not an easy one to work on.

airraptor

My Feedback: (66)

shoot me your address in a email and i will get one out to ya. i will send out a OS 46 to ya. You have to run a Jett muffler though. do you have one?

1QwkSport2.5r

I have the red Jettstream for my TT .46 Pro. I dont know off-hand if the TT has the same bolt spacing or not. I could make a bridge adapter like I did on the Enya if need be.

What fuel do you use to get the numbers you get? I only run 5% nitro 20% castor in my engines as I havent seen a significant enough gain in power to run 15%, plus several of my engines are from Europe and dont like a lot of nitro anyway.

I'll send you a PM.

1QwkSport2.5r

I dusted the ss30 off, and ran it a little bit. It ran really well as I expected it to.. This is a very nice little engine.

TT .46 Pro stock muffler
5% nitro / 20% castor
McCoy MC59 plug/2 washers
APC 9x5 sport prop
70°F air temp, humidity 90%, dewpoint 65°F

Muffler baffle installed - 14,800rpm peaked
Muffler baffle removed - 15,210rpm peaked

Idle speed was reliable at 2700rpm or so, but the engine isnt broke in all the way yet. It has about 3/4 gallon through it on the test stand. I wouldnt be surprised if this engine will idle down to 2400-2500rpm when it breaks in good. Off the shelf I didnt touch the airbleed and it transitioned like a dream.

This engine doesnt have ideal pipe timing, but it definitely responds to a larger muffler. The baffle in this muffler has been slightly modified. I used a dremel and sharpened the edges of the "fins" of the baffle. They were blunt and square, I just sharpened the edges to improve flow. I'm not sure if it makes a difference or not, as I didnt test it before the modification. Fuel draw is good, and muffler pressure is adequate as it needles very well. At peak, it takes 5-6 clicks before rpm drops.

aspeed

What does it rev with no muffler?  I always check mine on the stand this way as a starting point because mufflers are so variable. I like your clip for shutting off the fuel.  I have one too and like it but can't find them anywhere.  I assume it is from a medical store.

1QwkSport2.5r

I haven't ran this one without a muffler yet. I venture to guess it will rev 14,000 or so open faced on the 9x5. The stock muffler is quite small, more for a .15-.20 sized engine. Its also quite loud. If I get some time tomorrow, I'll run it open faced to see what it revs on it. Comparing the Enya .30 muffler to the TT .46 muffler, there's a significant gain in power.

The fuel shut-off clip is actually a part that came on my 1/8th scale R/C monster trucks and I have one on my 1/10th scale Jato stadium truck. I only use these clips to shut fuel off on the little engines because the tank ends up being a little above centerline of the spraybar. Initially, I was running a homemade bladder tank that the little Enya had a hard time drawing fuel once the bladder got down to 1/2 full. Running a normal tank with a felt clunk it runs fine but with a full tank, it will siphon into the carb some. One problem with this carburetor is even with the throttle barrel closed all the way, the engine will run off the air coming in through the airbleed hole. The airbleed hole is too close to the spinning prop to plug so shutting the fuel off works best to shut this one down.

This engine is running in still, and I'm sure the rpm will pick up a little more. I ran 16oz through it today, so its almost at a gallon now. I forgot I had some 25% castor fuel mixed up so I switched to that fuel today and it ran a little better than it did on the 20% fuel.

1QwkSport2.5r

I got bored this morning and used Pé's prop power calculator and plugged in some values, what I found is somewhat interesting. The Enya manual suggests propping the SS30 for 12,000-13,500 on the ground for best power. I assume peak torque. On the stock muffler it makes .528hp (using 1.24 prop constant) turning a 9x5 APC at 13,560. With a .46 muffler, it turns the same prop at 15,200 for .74hp. My math looks to be off, but I am getting a 41% increase in power from the stock muffler to the 46 muffler turning the 9x5. The engine makes the same HP turning the 9x5 as it does turning the 10x6 on the stock muffler, but on the 46 muffler the engine makes 20% more power - .528hp vs. .633hp. If a larger muffler yet would get the engine to 16,000rpm on the 9x5, it would be up to about .87hp.

Does this sound right?

1QwkSport2.5r

I finally got around to trying the .46 size red Jettstream muffler on the SS30 Enya. Nice gains over the TT .46 muffler I was using.

All APC props, 34°F air temp, MC59 glow plug, 5% nitro 25% castor

9x5 - 15,950rpm
9x6 - 14,800rpm
9x7 - 13,500rpm
10x6 - 13,050rpm

Compared to the numbers obtained using the stock Enya muffler, this engine has gained a lot of rpm from the various muffler changes. I'm impressed.

9x5 - 2,390rpm gain
9x6 - 2,230rpm gain
9x7 - 1,830rpm gain
10x6 - 1,940rpm gain

I am really impressed with this engine. It is by far the most well-mannered engine I own.

buzzard bait

Amazing. The figure for the 10x6 would be very respectable for a sport .40. I guess it's like putting on a mousse can.

Jim

1QwkSport2.5r

Not bad for a 9oz engine (minus muffler)!

I'm finding 2-strokes really like large volume exhaust. I'm sure there is a ceiling of how far it could go without going the tuned pipe route.

aspeed

Is it better than open exhaust?  That is the real test.  A pipe will do that.  Some mufflers do, but most don't.

1QwkSport2.5r

Stock muffler numbers are much less than open faced, about 1,500rpm less. The next time I get a chance, I'll try the same set of props all open faced.

1QwkSport2.5r

Enya SS 30bb Open Faced Exhaust-

32°F, 5% nitro 25% castor, McCoy MC59 glow plug, APC props

8x6 = 17,010
9x5 = 15,780
9x6 = 14,650
9x7 = 13,830
10x5 = 13,020
10x6 = 12,290

I have not run the 8x6 on this engine before, so when I get around to running it with the muffler, I'll try it.

Gains favoring the Jett muffler, the loss favored the open faced exhaust.
9x5 = +170rpm
9x6 = +150rpm
9x7 = -330rpm
10x6 = +60rpm

Conclusion: The Jett muffler gets very very close to open exhaust AND its a LOT cleaner.

aspeed

The 9-7 is slower with the Jett muffler, but in the air with less load it may come on the pipe as the load will be much less with the high pitch.

1QwkSport2.5r

That is certainly possible. I doubt this engine will be in the air anytime soon, I haven't earned my wings yet.. Thats okay though.. I have a few airboats I can run it on; that is when I have time.