For your viewing pleasure and my knowledge I present you with a cut away of the OEM muffler for the sedan!







There is a resonator actually in the outlet portion which measures about 4" in length.

The output side is 2.5" OD
The inlet side is about 1.8" OD but necks down to 1.6" OD
The exhaust has to exit the Swiss cheese portion of the pipe before it can exit the muffler. The other end is like a big resonace chamber with no exit.

 

pretty cool! i was wondering what the inside looked like

 

Next step is strapping it to the dyno and doing pulls with and without the muffler to see if there are any gains. I already modified the rest of the exhaust to be dual 2" to an x pipe which then opens to dual 2.25" back to the factory mufflers. The mufflers will be the limiting factor here but it will be interesting to see how limited they are if at all.

 

subbed..

 

Very cool. Thanks

 

Don't think they'll be limiting at all since they're cut open now






































j/k.........................should be interesting to see how this goes

 

Dyno session scheduled today for baseline pulls 2-3 then dropping mufflers and running 2-3 pulls.

Current setup:
OEM cats
Modified HR y pipe turned into x pipe all 2" piping (OEM sedan is 1.8")
Coupe resonators which are also 2" (OEM sedan resonators are 1.7" internal)
Then it goes to 2.25" back to the OEM mufflers

Frankenstein exhaust for the win...let's see what happens in a few hours

 

Better believe I'll be waiting for this.

 

Dynojet

Mods:
Custom exhaust as listed above
Mishimoto post maf tubes
R2c drop in panel filters

I will post numbers shortly but it appears a muffler delete on my setup is gaining around 5-6whp and wtq across the entire rpm band

 

So 2'' piping from cats to a X pipe? Then, 2.25 from X-pipe through the mid pipe to the mufflers?

Nothing else other than the drop in air filters? I wouldn't be surprised if you were sitting about 10-15 whp and wtq over stock assuming the drop ins are contributing to more power similar to K&N drop ins.

 

Ok...you guys are going to be excited...it's better than previously posted

From about 6500-7500 rpm
Without mufflers gain about 10whp 8wtq

Below 6500rpm
Without mufflers about a solid 8whp 6wtq everywhere

This is my pre muffler setup

 

Is there rasp, and I assume typical 1500-1800 rpm drone, no biggie there. Good results for sure, been wanting to do something else w/ my Y-pipe section so this is good news.

 

With the OEM mufflers on it sounds beautiful. You can trust my word because I am very picky, I drive 100+ miles daily and work out of my car mostly. Can't have anything with drone or rasp.

This was just a dyno comparison. I will post sound clips when I finish modifying the exhaust to delete the oem mufflers.

The dyno was very generous. I baselined with 306whp 242wtq and finished without mufflers on at 316whp 256wtq roughly. When we did a cool run with mufflers and a cool run without mufflers is when we got the results I posted in the earlier post

 

Did you have to modify the coupe mid-pipe to fit and is it all 2" piping?

 

Coupe midpipe is 2" piping...it's quite modified since I cut out the y section. The rear will not bolt to a sedan muffler either...don't attempt it without a good welder