Looking to set up a 40% 3W Extra with a 3W 157 on canisters. Already looked into the 3W stuff but I wanted to see if there are any other options out there before I start buying stuff. Any ideas?

Stick with the 3w/pefa mufflers for the 157, that motor smokes with those.

MTWs are available through DA and Troybuilt (TBM).

Desert Aircraft has the MTW's but you will probably have to get the headers from one of the 3W dealers.

I think buying aluminum cans could become a huge waste of money. My new style ignition equipped 3W ran on one cylinder for a while before each flight. This running on one cylinder caused extra vibration in the plane, which I believe led to premature fatigue of the headers and cannisters. The result was that by flight 21, header #1 broke. By flight 25, canister #1 broke the baffles loose internally, by flight 40, the second header broke. Around flight 45, 2nd canister broke. Anyway, after this, I would only suggest buying the MTW steel canister set. Hopefully, the MTW's will stand up longer over time than the aluminum PEFAs.
Jim W.

I keep thinking that I should just go with standard mufflers to save myself from any headaches but keeping it quiet is something I have to serioulsly consider as it will be my Imac plane. It probably won't be long before we start seeing houses going up around the field as well.

Well George,

I have a fresh comparison for you. I decided to install Johnson mufflers after this last contest when the 2nd canister failed, at this point not wanting to spring for the MTW complete setup. After leaning the engine quite a bit for operation with the mufflers, my very old 3W 150 TOC with walbro carb and 6.0V ignition turned the Fuchs 33x12 at 5320 rpms. The sound was obviously louder than before, but this performance was - call it identical - to anything before with the canister setup. Also, I was able to fly 3 Advanced sequences, a couple screw-around maneuvers, and land with plenty of reserve (50 tank, D.A. Extra 260). My friend Juan R. was flying his Extra 260 with same engine, but equipped with the PEFA canisters, same prop, and his tached 5340. No surprise, in the air, his was quieter too. The noise on mine was less than obnoxious. I'll use this setup until either field or competition restrictions demand otherwise. Next step for me is to just go to a 3B prop - probably later in the year after I setup my E-pattern planes.
Jim W.

Hey Jim,

Thanks for the comparison. I did some checking and none of the local contests that I will be attending have a sound score. The ones that do, I'll just have to manage the throttle and if I get dinged a point than oh well. I'm flying basic at this point so I'm just trying to have fun and learn as much as possible. I think I'm going to keep things simple for myself and run standard mufflers. I'll keep my eyes open for a deal on a used set but right now I'd be better served spending that money else where. Thanks for the replies.

George, that 157 will make a lotta noise with standard "mufflers" They run the best with the PEFA's, never have broken anything on the 4 or 5 different sets I have/had. I am using Greves pipes on my157CS in the new Bipe, just to see what happens, have a set of PEFA's if they don't do what I want. There was a set of new PEFA's on RCU a few days ago. WIll report on the performance with the pipes when we get the airplane done.

Tom

Hello Tom,

Thanks for the heads up. Up until today I was under the impression that the standard mufflers would fit within the cowl until I saw a picture of the same plane with the cowl opened up to clear Johnson mufflers. So today the idea of canisters is back on the table because I don't want to hack up the cowl. It looks like I'll have to cut a hole to clear the carb as well. If I was to remove the snorkel and plumb the line from the carb plate to the inside of the motor dome, that shouldn't affect the way the engine runs right? I'm hoping this will allow me to finish the install without making any holes but I haven't checked if the carb will clear without the snorkel so we'll see. In any case, I'm going to go with the canisters and give it a try. This being my first time using them, what should I expect as far as tuning the engine? It's a brand new 157cs and I'm wondering if you typically end up being a little leaner or richer with canisters as opposed to standard mufflers? Thanks again.

George, sure, you can toss the intake horn and run the hose inside the fuse, I don't really think the horns are worth having. As far as tuning, start at the factory settings, most of mine were the same, cans or "mufflers", that was on my 150's, the 157 shouldn't be any different. And I finally got a DA 150 to put on the Super Extra, couldn't pass up the deal, this was after I got the 157!! Sent it to Mark for the Sala mods first thing, so we will see how it works, got a set of MTW's for that one. That left me with the 157 and no airplane, so the 41% Trueworthy Pitts was born!! Can't wait to get it in the air! Will start with a 32-10 and probably go to a 32-12 to keep the noise down after break-in.

Tom

Thanks Tom. I appreciate the info. I'm going to check how much clearance I have without the horn on the carb and hopefully mount the motor tonight. If it turns out that I still have to cut a hole in the cowl than I may end up mounting my DA150 since the carb doesn't hang down as much and save the 157 for a 46% Ultimate. I have an airbrushed cowl on the Extra and I would really like to keep it as clean as possible. Anyway, I'll have this whole figured out by the weekend. Thanks.

A DA on a 3W plane???? Don't let them find that out!! HeHe. Let me know if it fits, I'm sure it will without the snorkel.

Originally Posted by Supermod56

A DA on a 3W plane???? Don't let them find that out!! HeHe. Let me know if it fits, I'm sure it will without the snorkel.

That would be interesting wouldn't? I'm sure I'd hear all sorts of comments. I could leave the 157 decals on the cowl and see who notices that its a DA after they've heard it run. I'm sure I'll be ok without the horn though. Canisters will be ordered tomorrow so I'm on my way to getting this finished.