Maybe this is a dumb question, But I have noticed somthing strange about aftermarket motorcycle exhaust, When installing a muffler such as a glasspack with a louvered core on a cage, The louvers always face the inlet end, Any aftermarket bike exhaust with louvered core or baffles they face to the outlet. Now maybe I'm missing somthing here, But the louvers facing the outlet does nothing what so ever for sound, Why have them that way? I've noticed this on V&H, Rush, Reinhart & so on. I was even at my local exhaust shop last week have some flowmasters put on the PU and ask the owner what was his take, He said he had never noticed it but it made no sence to him to install them backwards other than maybe a little more flow. But then like he said, why not just use straight pipes in that case. Any Ideas?

 

I think you mean "sense".

 

Thank you, Yes I mean sense.

 

I'm not sure why. It's a good question. I hope someone responds. I'd like to know the answer too.

 

would be interesting

 

Ya dont have ta be so pacific

 

I put some Sampson shorty baffles on a set of Street Sweepers and the louvers faced both ways. Every other louver was flipped.

 

OK, so I went to Lowes and got some of these louvers y'all are talkin about. They seem a little big for the exhaust ends - did you just cut them down?

 

Is Atlantic Ok with you!!

 

First, nice to hear you put REAL mufflers on your truck! Now, as you noticed, many glasspacks, which includes pretty much every single moto muffler out there, as well as most automotive aftermarket mufflers, have their louvered core facing one direction, if they're not the simpler perforated core (these can be installed either way with no change). When the 'open' ends of the louvers face the engine, it makes the muffler somewhat quieter, and more restrictive, because more exhaust gas goes into the packing material. No matter what, glasspacks are surprisingly restrictive, due to the physics of exhaust gases, and the sound/heat energy. When the louvers face 'backward', the exhaust flows a little more freely, and less sound energy is absorbed. Glasspack mufflers have been around for about 100 years now, and have not really changed in that time.

Just to plant a seed, I have heard a strong rumor that we're close to releasing a Harley muffler... I know nothing about it at this point, but it ought to blow anything else out of the water, just because it'll be a Fl0wma$ter! As they become available, information will be on our website, and I'll post what info I have here.