I would have sworn I'd seen a writeup on this, but cannot find it anywhere. Can anyone point me in the right direction? Anyone aware of a dyno comparison between stock and the flapper removed?

TIA

 

It's not the flapper you remove (you can to reduce the vibrations afterward) but the pipe that connects the two side chambers of the muffler.









Also, I did a dyno comparison in DLL.



Darker lines are the "after."

 

How did you know where to cut? Looks like you nailed the locations perfectly.

 

nice gains considering what was done.

 

Rock on dude! That's exactly what I was looking for.

 

what does it actually do?

 

How much louder did it make the exhaust?

 

Take a look here at the guts of the Evo X muffler: http://www.worksevo.com/store/produc...roducts_id=502

By removing that pipe, you bypass that convoluted internal routing and allow the exhaust to flow into the muffler and directly out the tailpipes.

You can definitely tell the muffler is free flowing after the mod. Has a nice growl, but hardly louder than stock.

http://s159.photobucket.com/albums/t...t=100_3040.flv

That's a crappy vid clip with lots of BG noise, but you get the idea. Nice and subtle still.

 

Anyone know what the stock muffler is made out of? Stainless? Galvinized steel? Thanks

 

Now a days I think all cars have stainless, they last a lot longer!

 

seems a lot of work to do by yourself.. prob would recommend a shop to do this lol

 

It's definitely stainless, but probably crappy T409 (since it was rusting already). I didn't have any stainless wire, so I just welded it back up with mild.

Not really... took me no more than 30 minutes to do the whole job. The muffler part itself takes 15-20 min at most. All you need is a sawzall and a welder. Easy peasy

But then again I tackled a clutch install on the X in the same exact spot in my driveway... I'm just dedicated and cheap.

 

noob question here, no CELs?

 

Shouldn't cause any CEL. You're pretty much home free after the back O2 sensor.

 

Mendo, just noticed you're in Dallas - Denver at Evo Dynamics is doing mine.