Has any of you ever seen the inside or know what the inside design looks like in the stock GSR mufflers? reason why im asking is becayse im probably gona go 2 1/2 - 3 inch exhaust from cat back and cut a bigger inlet to the OEM muffler to weld a 2 1/2-3 inch piping to it. but im not sure on what the design looks like so i can tell if its a possibility to do so. And maybe put a cut a 2 1/2- 3inch outlet with a new tip.

 

bump..anyone have any answers? or heard of this being done..

 

Stock Integra muffler is a typical 3 chamber "chambered muffler" design.

Increasing the opening and exit size won't do much, if anything, since the internal passages will remain the same size.

Not an Integra muffler, but they follow this basic design:

 

thanks man. do you or can you find out(tried googling) how big the chambers are? that was my main concern..because if i make the inlet/outlet bigger it would serve no purpose if the chambers are 2 inch diameters. thanks.

 

If you're increasing exhaust size, just buy an appropriately sized new muffler. Its not going to be worth it to hack up a chambered muffler, they're not performance oriented to begin with.

The chambers are large, but the passages between them are the exact same size as the inlet and outlet (or smaller, as seen in the above photo), which is why opening up the inlet and outlet won't do anything.

 

thats what i was trying to find out. okay answered my question thanks. i just didnt want a noisy muffler...do you guys know if those borla mufflers are pretty quiet? i want a stock looking muffler too. the borlas look close to stock. dont want no twin loop ugly *** muffler or some big *** str8 through design muffler...just stock looking and quiet..yet with a better flow.
the reason why is cuz im going to rebuild my block..with 81.5 type r pistons, and my buddy is trading me his stage 1 skunk2 cams for my rc injectors. so i wanted to increase the exhaust flow a little. im going to tune it for smog legal purposes with a 14.7 f/R and still gona be using a caty..probably a high flow.

 

bump: anyone know how loud the borla mufflers are?

 

try vibrant theyre stock looking and kinda quiet but with a straight thru design...even tho my theory is that gsr mufflers are an upgrade from ls mufflers. it flows just a bit more. thats what i read somewhere i just forgot where.

 

You could always get a Type R. Supports decent hp and is still OEM...or JDM RSX-R, S2k, etc. You could also buy a chambered muffler that will support just about any hp you want, its just not the "import" thing to do.

I actually have a borla on my Integra, loud is relative to other factors like are you running a cat, do you have resonators installed, what type of resonator, what type/model muffler (as even borla makes several styles). I'm fairly happy with my setup, no cat, 2 resonators and the borla muffler....pretty quiet for the most part. Interstate drone still gets to me though....then again I have B16 gears w/ a 4.785 FD and the **** is sitting at 4700 rpms too.

 

ok i know this is a dead thread.

but i camed for a random question
if you gut the inside of the stock muffler
whats the pro and cons of taking everything inside of the muffler out?

 

Pros:
potentially increased flow

Cons:
no muffling, and it might even be louder than straight pipe (echo chamber)
potentially decreased flow without anything to guide the exhaust through the now empty chamber

 

Hmm, a professor in fluid dynamics could tell you.

Basically it will be less effective than a straight muffler delete (since going from a small diameter opening, to a large one, and back down to a small one increases fluid resistance). Noise will be louder, but then again, less than a straight muffler delete.

It wont be an echo, since the air exiting will be under high pressure (low noise) as opposed to low pressure (high noise).

Im assuming your goal is to increase performance while essentially appearing stock, my advice: get an apexi NOIR or something because literally opening a muffler and ripping the internals will cost you a LOT of money... unless you are doing this for a school project or something