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-   Century - Predator, Hawk IV, Falcon, Raven (http://www.rcuniverse.com/forum/century-predator-hawk-iv-falcon-raven-205/)
-   -   Choosing a muffler.. (http://www.rcuniverse.com/forum/century-predator-hawk-iv-falcon-raven-205/8823581-choosing-muffler.html)

Broncoflyer 06-03-2009 07:46 PM

Choosing a muffler..
Hi all, quick question......
Bought me a Century 30 size airwolf last year that had a OS 46 fx engine. (remember me Scyclic?)It flew ok except for newbie pilot error..... I recently bought the Century 30 mechanics and I am now flying it as pod & boom. When i got the mechanics I also asked the dealer for a good muffler as well since all i had was the century scale muffler which did a pretty good job of blocking access to the idle mix screw on the carb. They sent me the" Silent Power Tri-flow muffler 50". Problem is that I cant seem to get any decent head speed out of this engine now. I cant try the square scale muffler again to rule out the size change cuz "SOMEBODY" stripped the threads on the darn thing somehow. Anyways, the mechanics kit I bought came with a 30 size muffler which i think will fit but before i change it over I was wondering how the muffler affects engine performance. Is it a case of getting the right size muffler to give proper fuel pressure or for the right amount of engine back pressure, or a combination of both? The 30 muffler that came with the kit is way way smaller than the tri flo and no specs are given on it. Basic question is if I bolt on the kit muffler to try it can I blow my engine? Wife wouldnt be too pleased with my next purhase if it does.......

Thanks fer any input you can give


rotor09 06-04-2009 11:05 AM

RE: Choosing a muffler..
The new 50 muffler you have should work better on your 46 then the restrictive 30 size muffler that comes with the kit. But you will definitely have to re-tune both needles. I would expect more so on the hover/idle screw.

That would also mean a change in the throttle curve settings.

Are you using the stock 30 gear ratio? You may want to seriously consider changing the gearing to that of their 50 size Raven (using the 14T primary gear pinion instead of the stock 30 size 13T pinion. I haven't ran an OS46 in a number of years, but I know they ran better on a 9/1 ratio then on the stock 30 ratio of 9.76/1.

Broncoflyer 06-08-2009 10:59 PM

RE: Choosing a muffler..
Thanks rotor,
I'm gonna have to go for the alternate drive gear as you suggested. With the carb set up as good as i know how ( not very), and a new throttle curve it still doesnt seem to have much jam. Not compared to vids I've seen of these things on the net. I'm still havin a blast with it so no biggie. thanks for the help


Broncoflyer 11-10-2009 11:56 PM

RE: Choosing a muffler..
Just a follow up on this post, a couple of months late but oh well,...
Did some follow up and my local online hobby store manged to get this responce from a Century rep..

"Yes, the Raven has a 14T pinion - this gives it a ratio on the Raven with its gray primary gear of 8.73 which is better for larger engines that do not have to turn up as high to producce power then do the smaller (32) engines.

That is why the Hawk with the 13T/black primary gear resulting in a 9.76 ratio is generally considered better for the smaller engines that have to rev more for their power.

Using the 14T pinion on the Hawks black pinion will give the 9.1/1 ratio of the early Falcons. Weather this is better for the current OS37 engines is still debatable, as I find they love to rev for power also.

But for the retail cost of the 14T pinion (CN2224) of pnly about $15.00 many like to experiment with it."

for my hawk pro I bought the raven pinion and installed it. took a little bit of doin' to get it on there.I had to remove one of the spacers under the oem pinion , then I had to file the pinion shaft set screw flat spot cuz the set screw on the new pinion sits a little lower on the shaft. I also had to carve a bit of plastic out of the mainframe body to fit the wider pinion gear base diameter. Gear mesh to the main gear was a little on the tight side but i figured that it turned freely enough so it would be ok. Result was alot more jam with my OS46fx-h. Very happy with the change so far... just to let you all know how it went for me....


jcervantes11 02-17-2011 05:34 AM

RE: Choosing a muffler..
You can buy a toki 40 muffler. These engine/muffler is availble. Muffler cost around 39 bucks or so.

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