muffler design idea

[Sam_Q]

after managed to deceive my way out of an epa 'vehicle too noisy' pin I am thinking of making my car quieter, good for my sanity too. I still want a tottaly non restrictive exhaust but not be loud and it seems that theres no much on the market to help me. So I had an idea, first here are some princibles that I think apply:

- a muffler or resonator with a straight perforated section of the pipe through the middle will not block any flow regardless of length

and

- the longer the pipe is with with sound deadening material around will block more noise

if I am wrong on this please correct me


so if the pipes inside the muffler are the longest possible lengths and only the straight sections are perforated then it will be its quietest

so I am thinking of making the pipe just afetr my diff beak into 2 pipes of an equal cross section area (CSA) combined, and then internally to 4 individual 1.25 inch pipes.

Heres is my drawing:



I am pretty sure it wouldn't cause any extra restriction but would it stop the nasty raspy sound that my 20v makes?

also I am thinking of using rock wool for the baffling

[Mos]

Every split will cause a restriction, when compared to not splitting, but yes, it should yeild lower noise levels.
Mos.

[Sam_Q]

I cant really see the spits causing much of a restriction considering how I make collectors, heres one from my extractors:

[Sam_Q]

even with this design do you think it will have any extra friction or something?

[river]

Hi,

Muffer???? Hehehehe....

http://www.urbandictionary.com/define.php?term=muffer

seeyuzz
river

[Sam_Q]

"A term used to describe a young male who spends eccessive amounts of time with his girlfriend, as opposed to spending time with his friends"

hahahhaa, thats not quite what I had in mind

thanks for the correction dude

[Billzilla]

I guess it'd work a bit better than a regular resonator-type muffler.

But don't forget, we have very good evidence that I'm crap at figuring out how muffler work.

[Sam_Q]

hahahaha, well I did think your idea was great, I dont think anyone anywhere knows why yours didnt work

[Mos]

Splitters work differently to collectors and, as counter-intuitive as it might sound, a knife edge is not the best shape for cutting into a fluid (exhaust is a fluid).
Think tear drop shape - which end goes where?
Mos.

[Sam_Q]

yes I have heard about that, the right hand flange is meant to be just after my diff and the left twin outlets, I dont think I would be able to get a die grinder in there and blunten that edge.

[Mos]

I don't mean blunting the edge.. I mean a curve. There are some guidelines about creating splitters but I'm not exactly sure what they are, but IIRC the curvature of the leading edge is something like one of the smaller diameters (or maybe the larger.. not sure). Any fluid dynamics people around?
Mos.

[Sam_Q]

yeah I know, when I said bluntening it I meant bluntening it into a round shape. I will ask someone who should know about this sort of thing.