Scuba

I need some muffler help. I am planning to use an OS .91FX, inverted, to pull this plane around the sky. Unfortunately, I can't seem to find a pitts-style muffler for the .91. A call to product support at Top Flite yielded the following suggestion: use their in-cowl system, but it needs to be "opened up" or the engine will overheat.

I have two questions: 1. Does anyone out there know of an incowl system that will work wothout modification, and 2. Does anyone have experience modifyingthe Top Flite muffler for use on an OS .91FX?

beardking

My Feedback: (4)

Here is a Bisson Custom Mufflers setup for the OS 91 FX. Don't know anything about how well it fits in your plane, just did a search and found this. http://bissonmufflers.com/en/muffler...ting_id=114048

Kirk RC

My Feedback: (4)

Heres a perspective having built 2 TFP-51's with a third under way, Also the owner of 2 OS FX-91's. Read the thread under the engine section on all the troubles with the FX overheating. I tried to use the TF incowl muffler with a ST-90 . I drilled it out etc and it just couldnt work with a 90 size that runs cool, the FX runs hot, ( if you can get it to run at all). IMO your going to spend alot of time and $ building a great kit and than make a BIG mistake on the most important component. The best set up is a 120 Four stroke, I have both the OS pumped and nonpumped versions in my 51's and they work perfect! The head purtrudes alittle out the bottom, maybe half inch, and the muffler out the side of the lower starboard cowl but at 5 feet away you cant tell. Go to the pic. gallery and look at my 51 under Kirk RC. I wouldnt put the FX91 and TF incowl muffler in my 51's if you gave it to me for free, on the plus side it will make for a good pic in the crash section. Just a few thoughts, good luck, its a super warbird kit.
Kirk rc

Kirk RC

My Feedback: (4)

Scuba,
I didnt want to appear to be a smart a-- with my comments about "crash pics". Just wanted to give you a real heads up based on my experience. Maybe you can get the combo to work where others have not just FYI.
Good Luck
Kirk RC

Scuba

Thanks for your input, Kirk. I'm just stubborn enough to try to make the .91 work.

Is there anyone else out there who has tried to make the .91 work in this plane?

RCHYFLYER

My Feedback: (1)

Can you mount the engine horizontal? I have a TF corsair with 91FX in it (See Gallery pic) the muffler was a slimline pitts but do to a flame out it broke the tubes on impact so I changed to a Jtec and it has flexable tubes.

Ernest-T

My Feedback: (7)

I mounted a Saito 150 inverted on my 1/7 scale TF P-51. I modified the bottom of the fuse behind the cowl to make a channel for the stock muffler. The setup was almost invisible from normal viewing positions, and you really didn't notice the engine head unless you were on your belly. I'll see if I can find some photos and scan them in.

Unfortunately, an elevator control linkage failure resulted in the early demise of my P-51, but the Saito 150 was very adequate power!