Need to quiet down my DL 50
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From: Phoenix,
AZ
Hi everyone. I posted this on the DL thread but didn't get many replies. Anyway, the stock muffler on the DL 50 is LOUD. My field is issueing a 94 decible rule and i don't blame them. Some of the guys out here are running REALLY loud engines. Many running straight pipes and it is just hard to listen to. I would like to hook something up to my dl to quiet it down but i really don't want to spend almost the price of the engine for a exhaust pipe. LOL. So, what is out there that will quite this engine down alot and have minimal RPM loss at a resonable price.
Thanks
Cameron
Thanks
Cameron
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From: Starkville,
MS
I have a Pitts "Silent Beauty" muffler for my DL. I haven't taken any decibel readings but it's noticeably quieter than the stock exhaust, cheap too. You can get them from Troy Built Models: http://troybuiltmodels.com/Mufflers.htm
#5

ORIGINAL: Cambo
Interesting thaught. Okay, so what exactly do you need. I want this thing to be as quiet as possible.
Interesting thaught. Okay, so what exactly do you need. I want this thing to be as quiet as possible.
Mark
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From: Phoenix,
AZ
How do the wrap around mufflers that TLparker suggested work. After looking over the model I am not sure there is much if any room for a canister setup. The problem is i would have to move the fuel tank back to make room for the canister but there is really no room for the fuel tank to move back the way the airplane is biult. I also might be looking at a 3bladed setup?
Thanks everyone
Edit: I did some research on a canister muffler in the plane the DL is in. (GP 27% cap 232) As far as I know it can't be done. There simply isn't the space.
Thanks everyone
Edit: I did some research on a canister muffler in the plane the DL is in. (GP 27% cap 232) As far as I know it can't be done. There simply isn't the space.
#12
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Combine a 3 blade prop with a J&A or J-tec wrap around Pitts and you should be toeing the line. Sometimes moving the muffler outlet will alter the level just enough if they don't make it already. Move the outlet(s) with stack extensions of your choice.
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From: Phoenix,
AZ
So my muffler options are the silent beauty, jtec, jtec "large". I guese the large version is suposed to silence the engine more than the normal one. The Jtecs are pricey though.
So far i have seen a few different 3 bladed props, xoar makes some
http://www.espritmodel.com/index.asp...OD&ProdID=6387
I am a little worried about wood for a 3bladed setup
also mejlick makes some
http://troybuiltmodels.com/newsite/p...mejzlik.html#3
Not sure of any others. Could anyone post some links?
So far i have seen a few different 3 bladed props, xoar makes some
http://www.espritmodel.com/index.asp...OD&ProdID=6387
I am a little worried about wood for a 3bladed setup
also mejlick makes some
http://troybuiltmodels.com/newsite/p...mejzlik.html#3
Not sure of any others. Could anyone post some links?
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From: Superior,
AZ
Before you go and buy silent beutys do a search here in the gas forum.A person here already bought some and they didnt work to quiet his down and he was displeased.
#16

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Noise can be reduced by simply using a good muffler and keeping the tip speed down. A good muffler will not hurt performance but slowing the prop often will. It is surprisingly easy to make a 50cc the quietest thing at the field, but nobody has the desire to do it.
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From: Fries,
VA
Cambo,
I suggest you get in contact with Pe Reivers. He can give you the exact information needed regarding Mufflers, Props, Noise, etc.
His prices are not bad, and shipping is not bad either. It will just take longer for the items to show up.
http://mvvs.nl/
I suggest you get in contact with Pe Reivers. He can give you the exact information needed regarding Mufflers, Props, Noise, etc.
His prices are not bad, and shipping is not bad either. It will just take longer for the items to show up.
http://mvvs.nl/
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From: Phoenix,
AZ
Thanks for all the help everyone. I am going to hold off a buying anything untill i take it too the field and have some club members determine if it is too loud or not. 94 decibles is not official yet.
If it fails i have got to find a better muffler and possibly better prop combo. Currently I have a 22-8 xoar. Would a 20-10 3-bladed xoar do the job? I think that would have a similar load from my understanding but turn a similar rpm.
So far, after doing a search, I haven't read anything bad about silent beauty mufflers but alsot haven't read much that is posotive. Just not much info about them.
Out of curiousity, are there shorter canister systems that exist? I mean why do they have to be so darn long?
If it fails i have got to find a better muffler and possibly better prop combo. Currently I have a 22-8 xoar. Would a 20-10 3-bladed xoar do the job? I think that would have a similar load from my understanding but turn a similar rpm.
So far, after doing a search, I haven't read anything bad about silent beauty mufflers but alsot haven't read much that is posotive. Just not much info about them.
Out of curiousity, are there shorter canister systems that exist? I mean why do they have to be so darn long?
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From: Gt.Yarmouth, UNITED KINGDOM
Hello.
The standard DL silencer can be easily modified to reduce the noise and with very little cost.
Just get some tube that is a tight slide fit into the existing outlet and blank off one end. Slide it into the outlet as far as it will go (blanked off end first ) then mark and cut it to the same length as the existing one also mark which part of the tube is actually inside of the cannister section.
Drill 4 x 1/4" holes evenly spaced into the new tube at a point that is inside the cannister body. You now have a restrictor that you can "tune" by adding more holes of varying sizes to acheive the desired effect. The 4 starting holes will be enough to get the engine to run. A little power loss will be inevitable.
The new restrictor is held in place by drilling a couple of holes thu' both tubes and secured with self tapping screws.
When you are happy with the "tuning" the fix can made permanent by smearing a little exhaust compound around the the restrictor tube as you finally fit it.
Good luck.
Mike.
The standard DL silencer can be easily modified to reduce the noise and with very little cost.
Just get some tube that is a tight slide fit into the existing outlet and blank off one end. Slide it into the outlet as far as it will go (blanked off end first ) then mark and cut it to the same length as the existing one also mark which part of the tube is actually inside of the cannister section.
Drill 4 x 1/4" holes evenly spaced into the new tube at a point that is inside the cannister body. You now have a restrictor that you can "tune" by adding more holes of varying sizes to acheive the desired effect. The 4 starting holes will be enough to get the engine to run. A little power loss will be inevitable.
The new restrictor is held in place by drilling a couple of holes thu' both tubes and secured with self tapping screws.
When you are happy with the "tuning" the fix can made permanent by smearing a little exhaust compound around the the restrictor tube as you finally fit it.
Good luck.
Mike.
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From: Gt.Yarmouth, UNITED KINGDOM
Hello Cambo.
I used very thin wall steel tube and silver soldered the end cap in place.
Have used this method several times to quiet very noisey so called mufflers.
If you arrange the baffle holes so that none point directly at the piston then quite acceptable results can be achieved.
I wonder if an alloy cigar tube could maybe be used, at least they are already blanked.
Best Regards.
Mike
I used very thin wall steel tube and silver soldered the end cap in place.
Have used this method several times to quiet very noisey so called mufflers.
If you arrange the baffle holes so that none point directly at the piston then quite acceptable results can be achieved.
I wonder if an alloy cigar tube could maybe be used, at least they are already blanked.
Best Regards.
Mike
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From: Phoenix,
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Out of curiousty, why do canister setups need to by so long and straight out the back. What if one was setup to go in the space that a "pitts" muffler would take up and have a header that bends around the cylinder? Any thaughts?
#23
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ORIGINAL: ukmike
Hello.
The standard DL silencer can be easily modified to reduce the noise and with very little cost.
Just get some tube that is a tight slide fit into the existing outlet and blank off one end. Slide it into the outlet as far as it will go (blanked off end first ) then mark and cut it to the same length as the existing one also mark which part of the tube is actually inside of the cannister section.
Drill 4 x 1/4" holes evenly spaced into the new tube at a point that is inside the cannister body. You now have a restrictor that you can "tune" by adding more holes of varying sizes to acheive the desired effect. The 4 starting holes will be enough to get the engine to run. A little power loss will be inevitable.
The new restrictor is held in place by drilling a couple of holes thu' both tubes and secured with self tapping screws.
When you are happy with the "tuning" the fix can made permanent by smearing a little exhaust compound around the the restrictor tube as you finally fit it.
Good luck.
Mike.
Hello.
The standard DL silencer can be easily modified to reduce the noise and with very little cost.
Just get some tube that is a tight slide fit into the existing outlet and blank off one end. Slide it into the outlet as far as it will go (blanked off end first ) then mark and cut it to the same length as the existing one also mark which part of the tube is actually inside of the cannister section.
Drill 4 x 1/4" holes evenly spaced into the new tube at a point that is inside the cannister body. You now have a restrictor that you can "tune" by adding more holes of varying sizes to acheive the desired effect. The 4 starting holes will be enough to get the engine to run. A little power loss will be inevitable.
The new restrictor is held in place by drilling a couple of holes thu' both tubes and secured with self tapping screws.
When you are happy with the "tuning" the fix can made permanent by smearing a little exhaust compound around the the restrictor tube as you finally fit it.
Good luck.
Mike.
(Above sentence is edited.)
Much better is to eliminate as much of the prop noise first by:
as first and most important resource, increase disk load without increasing rpm
so: Increase engine LOAD AT LOWER RPM
DO SO BY INCREASING PITCH, NOT DIAMETER. This keeps tip speeds down and away from near sonic fluid flow over the airfoil (air also is a fluid)
As second consideration, increase the number of blades. In a three bladed prop, narrower blades will perform surprisingly well! (disc coverage factor) There is a limit to increasing blades, so increasing diameter is next.
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From: Superior,
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ORIGINAL: Cambo
Thanks for all the help everyone. I am going to hold off a buying anything untill i take it too the field and have some club members determine if it is too loud or not. 94 decibles is not official yet.
If it fails i have got to find a better muffler and possibly better prop combo. Currently I have a 22-8 xoar. Would a 20-10 3-bladed xoar do the job? I think that would have a similar load from my understanding but turn a similar rpm.
So far, after doing a search, I haven't read anything bad about silent beauty mufflers but alsot haven't read much that is posotive. Just not much info about them.
Out of curiousity, are there shorter canister systems that exist? I mean why do they have to be so darn long?
Thanks for all the help everyone. I am going to hold off a buying anything untill i take it too the field and have some club members determine if it is too loud or not. 94 decibles is not official yet.
If it fails i have got to find a better muffler and possibly better prop combo. Currently I have a 22-8 xoar. Would a 20-10 3-bladed xoar do the job? I think that would have a similar load from my understanding but turn a similar rpm.
So far, after doing a search, I haven't read anything bad about silent beauty mufflers but alsot haven't read much that is posotive. Just not much info about them.
Out of curiousity, are there shorter canister systems that exist? I mean why do they have to be so darn long?
[DA100 and TBM silent seauty mufflers]



]. How much is a 3-bladed setup going to run me.