fisher1648

Can anyone recommend a good silencer for the Brison 3.2. I'm currently using an older A&M pitts style but it seems to be just a box with down-tubes. Doesnt really quiet it down much. I'm looking for something to mellow out the tone a bit and actually muffle it more.

Thanks, Eric

Bass1

If your firewall can accomodate a Bisson wrap around pitts muffler, you might give it a try. It won't be as loud as what your using. Don't forget to cut off the tapered down pipe tips if you need the extra power.

Flip and Fly

I had a Bisson pitts muffler on my Brison 2.4. Sounds mellow to me, not at all to loud, and yes do cut the curved muffler stacks, gain a little power and not much change in sound volume I think. Link http://www.bissonmufflers.com/en/index.html

FlyingPilgrim

My Feedback: (26)

Bisson, J&A, or Slimline should offer wrap-around pitts style mufflers that would all work better than what you have.

torqmeister

I use the Bisson standard side mount muffler. Cut 1" off of the exhaust pipes & it is still IMAC legal. If you use a Pitts style wraparound it will cost you about 400 rpm.

Flip and Fly

I just changed from the pitts muffler to the side mount ( Bisson) The pitts muffler came loose and departed from the plane[&:] On the 2.4 I did gain about 100 RPM, thats all. However it was louder and did not sound as nice. Not only that but visually not as nice as the muffler is visable under the front of the cowel.

I now use Hightemp silicon gasket maker on my muffler bolts, seems to work.

torqmeister

The other thing I like about the Brison inverted muffler is it only weighs 4 1/2 oz.

Bass1

Torqmeister, You say you removed about an inch off the pipes. Did you experiment with different pipe lengths? I just removed the pinched ends on my wrap around and was wondering if I would gain more power by removing more. You can see from the picture, I have plenty of pipe I could saw off. If I recall correctly my muffler weighs about 7 ozs.

CK1

My Feedback: (60)

Bass1 , I am running the Bisson Pitts on both of my 3.2 Brisons , one has just the tips cut off ,the other has only about 1 1/2 pipes protruding .
Both engines are turning NX 22x8 props at 7000 rpms . I have also swapped mufflers from one engine to the other and the readings didnt change.
So i would say that shortening the tubes any more than just removing the pinched part would not really gain any power or RPM's

Bass1

Thanks for the info CK1. Your experiment has answered my question. The last time I tached my engine I was turning a Menz 22/8 at 6900 rpms. It was a steamy hot day in August.

torqmeister

I cut 1" off of mine on a slight rearward taper. I tached it this weekend with a 3W 22/8(same as a Menz) at 7450 rpms. this engine has less than 2 gal of fuel through it & is still blowing soot.

Tired Old Man

My Feedback: (1)

If you're blowing a lot of soot out of that engine you may want to review your oil mix. 70 to 80-1 synthetic is good.

FlyingPilgrim

My Feedback: (26)

An added bonus of the J&A pitts mufflers is a nut welded on to support the body of the muffler. I don't believe the other mfg's have this feature, and it will help keep the muffler from loosening from vibration.

torqmeister

Silversurfer, I am presently running 80:1 mix, as per Gary's insructions. This weekend I leaned out the high speed needle 1/16, the soot output reducd by about 70%, & rpms jumped 150. This engine is screaming.

Richard James

The brisson 3.2 exhaust port is the same size as a quadra 42's. I bought a side mount muffler from Tower Hobbies for about $35 with 2 exhaust pipes that muffles quite well on my Brisson. To keep the muffler from falling off in flight get mounting bolts long enough to be on the outside of the muffler and use washers to cover the guide tubes. Drill the bolt heads and safety wire the bolts. My model has 400 flights and the muffler never has fallen off. Goodluck from Bigfly.