Using car engine muffler on a Four Stroke??
 

Hi guys

I'm getting sometimes a little extreme...but while looking at conrad´s site, I've found the following muffler:

And since I've lost the muffler of my Thunder Tiger F-75s during flight...I was wondering using this one...just fix it to the fuse and put a silicone tube between the manifold and the muffler... Since 4 Strokes are not so sensitive to mufflers...and since a new muffler cost more than the double of it...I was wondering..... What do you think?

RE: Using car engine muffler on a Four Stroke??
 

www.thundertiger4u.com have the replacement mufflers for US$20 and $10 for the manifold if you lost that too.

Their postage is very reasonable and takes about a week.

RE: Using car engine muffler on a Four Stroke??
 

Thanks custom PC...

Here in Germany it cost about 30€ plus shipping(Price I'm not willing to pay)...and I just lost the muffler, manifold is still there... If it is not a good idea at all..I'll may have a friend make a muffler for me (he has a lathe shop) or buy a ASP muffler instead =(...
In my plane (Black horse su-31 with engine at 225°), I have the problem that I have to use an exhaust deflector, and they don't last there...the silicone deflectors are after a couple of flights just not there anymore, and there are 2 reasons: High exhaust temperature...the silicone deflectors break just where the muffler sting ends....or because there is not enough space to attach the deflector...

With this car muffler I won't hae the problem of the deflector because the sting is already deflected

RE: Using car engine muffler on a Four Stroke??
 

Four stroke exhaust is much hotter than two stroke exhaust. The silicone may not hold up

RE: Using car engine muffler on a Four Stroke??
 

That is one thing, another matter is that car mufflers are really tuned pipes designed to push gasses back into the sylinder to "supercharge" a twostroke. It might work, but chanses are that this muffler will give too much back pressure so you will loose power or run too hot.

RE: Using car engine muffler on a Four Stroke??
 

OS and Magnum .70-.91 exhausts fit the F-75S.

Greg

RE: Using car engine muffler on a Four Stroke??
 

Pattern flyers ran two stroke airplane pipes on YS four strokes for years untill they made purpose built pipes for them. The tuned pipe on a two stroke is nothing more than a muffler on the four stroke.;) Forget the silocone and use a piece of teflon tubing which is also used by pattern fliers and sold by central hobbies.;)

RE: Using car engine muffler on a Four Stroke??
 

Do you still have the swept manifold? Some people prefer to fly with just that. I've seen manifolds tapped for a vent line to the tank.

RE: Using car engine muffler on a Four Stroke??
 

Yes I still have the manifold

I actually run the engine without the muffler after I lost it....I would say it delivers a bit more power...or maybe it was just the sound..which is about the same that with muffler....but the engine didn't work well at the transitions...and I saw lot of bubbles in the line, so I think it relies on muffler pressure to workt well and not just by suction... Another thing is that it is too short for the plane...the plane has a real fat fuse.

I thought it would be a good Idea to try this muffler since it's just 9EUR.... an ASP muffler would cost about 20 I think..and the original about 30...so I do my math hehe!...

How many times have you seen that the rear cap of the muffler...where is the gas exit...begin to turn???

Now I have 2 4 strokes and in both of them the rear cap turns and gets oily and black =(.

RE: Using car engine muffler on a Four Stroke??
 

I have had it happen to Magnum .91's and the good ol Saito old style muffler's. I tig welded all of them.:D