Muffler Baffling
06-29-2008 | 03:24 PM
#1
Thread Starter
My Feedback: (106)
Muffler Baffling
OK Guys,
I know it's prob. a thread on this but can't find it. I am gonna make a muffler for my 1/3 scale Fokker D-7. It will go on a ZDZ-80. I will need to put some WT. on the nose so thought I would do it in a useable way. Welding up the muffler will be no problem. Just can't see in my mind the best way to insert the baffling. Any ideas, drawings?? Thanks Hooker53
I know it's prob. a thread on this but can't find it. I am gonna make a muffler for my 1/3 scale Fokker D-7. It will go on a ZDZ-80. I will need to put some WT. on the nose so thought I would do it in a useable way. Welding up the muffler will be no problem. Just can't see in my mind the best way to insert the baffling. Any ideas, drawings?? Thanks Hooker53
06-30-2008 | 04:18 PM
#2
Senior Member
RE: Muffler Baffling
Make the inner works first, then the shell.
Where the baffles meet the shell, drill small holes. When tou "spotweld" those holes tight, you will connect the inner works to the shell and prevent rattles and interference.
Where the baffles meet the shell, drill small holes. When tou "spotweld" those holes tight, you will connect the inner works to the shell and prevent rattles and interference.
06-30-2008 | 07:07 PM
#3
Thread Starter
My Feedback: (106)
RE: Muffler Baffling
Pe,
Thanks for the return. Yes, I knew I wanted to make the inside first and slide it in before capping the ends. I'm just trying to understand mechanically how to set up the shell to give me the correct back preasure. Should I make it like a maze or just a baffle in front of the port with others offset above the port. The exit tubes with be at the top and the same size as the port area so I can run them out the side of the D-7. the 2"X4" tubing that I will be useing will be calculated to within 20% more Capacity then the Cyl. Not trying to go into a lot of science on this muffler, just a quite one that will not hurt the engine. Thank you so much for helping me here Pe. Still useing and loving my five MVVS engines by the way. Great engines.
Roy aka Hooker53
Thanks for the return. Yes, I knew I wanted to make the inside first and slide it in before capping the ends. I'm just trying to understand mechanically how to set up the shell to give me the correct back preasure. Should I make it like a maze or just a baffle in front of the port with others offset above the port. The exit tubes with be at the top and the same size as the port area so I can run them out the side of the D-7. the 2"X4" tubing that I will be useing will be calculated to within 20% more Capacity then the Cyl. Not trying to go into a lot of science on this muffler, just a quite one that will not hurt the engine. Thank you so much for helping me here Pe. Still useing and loving my five MVVS engines by the way. Great engines.
Roy aka Hooker53
07-01-2008 | 08:11 AM
#4
Senior Member
RE: Muffler Baffling
Thats a different question than the original?
You need to have about 8 times (800%) of cylinder displacement, not just 20% extra. (120%)
"a quiet one without hurting the engine" ? You will get rich if you can do that!
For least power loss, you need >1800% volume, placed directly behind a 120% volume first chamber. (dammed exhaust wave system) Forget the after muffler, and you have a "damned loud" system.
You need to have about 8 times (800%) of cylinder displacement, not just 20% extra. (120%)
"a quiet one without hurting the engine" ? You will get rich if you can do that!
For least power loss, you need >1800% volume, placed directly behind a 120% volume first chamber. (dammed exhaust wave system) Forget the after muffler, and you have a "damned loud" system.
