The Oldsmobile Connection

aron115 · Joined: 27 Nov 2007 Posts: 33

wow you guys are getting into some complicated stuff...so im hoping by cutting my cat out, which im gonna do tomorrow morning, i will get a loud sound and my car will sound like it has some balls. so lets say i take the cat off and i find its to loud, how could i get a sound like those tuners. deep sound. idk how they do it. are 4 cylinders like louder then a v8? caus my brother has a 4 banger and when he cut the muffler off, thing got really loud and i think it sounds good. why is it when i cut mine off, i dont notice a difference. that is a tad weird. so what exactly is the difference from a muffler and a resonator. i thought they both are suppose to make your exhaust quieter

oldsguy88 · Joined: 13 Apr 2008 Posts: 7

hey norm,

figure A in your little picture there are the Helmholtz resonators. They dont make anything louder, they just control the sound of the exhaust.

88 Coupe

DarkFox wrote: ........ run open headers ........
He doesn't have headers.

The following probably led to the confusion.

91buickman wrote: ........ find a set of headers ........
Waste of money. They will not be any louder than the original head pipe.

Norm

88 Coupe

aron115 wrote: ........ how could i get a sound like those tuners ........
When you hear one you like, ask the owner what muffler he is using.

aron115 wrote: ........ are 4 cylinders like louder then a v8? ........
Number of cylinders has little, if anything, to do with it.

Total displacement, compression, and cam timing, have a lot to do with it.

aron115 wrote: ........ why is it when i cut mine off, i dont notice a difference .........
Maybe, because the following,

oldsguy88 wrote: Take the Catalytic Converter off. They restrict the flow so much they basically act as a muffler.
is another 91buickman BS statement.

aron115 wrote: ........ i thought they both are suppose to make your exhaust quieter
They are.

In the '50s, luxury car manufacturers started using resonators to finish what the mufflers did not.

Norm

88 Coupe

oldsguy88 wrote: ........ They dont make anything louder ........
Yes. They make it quieter (opposite of louder) which is not what the OP is looking for.

Thanks for making my point.

oldsguy88 wrote: ........ they just control the sound of the exhaust.
Yes. They make it quieter by adding to that famous Flowmaster restriction.

Norm

aron115 · Joined: 27 Nov 2007 Posts: 33

yeah so i took the cat off and i got a much better sound. i just need to hold the exhuast up there a little better. its draggin right now and thats no good. gonna pick up another strap to put on in the back. i didnt have to time to make it go all the way back yet. still working on that. the cat was basically acting like a muffler. which is dumb. probally plugged up a tad or something. looks pretty old. i got a nice collection of cats going now. cant wait to take them in and get some money. i heard the older ones are worth a lot at the scrap yard

91parkave · Joined: 29 May 2007 Posts: 516

88brain cells wrote: .....Maybe, because the following,

oldsguy88 wrote:
Take the Catalytic Converter off. They restrict the flow so much they basically act as a muffler.

is another 91buickman BS statement.

At least get the right person. :wink:

anyways.....back to the header comment....Ive installed long tubes on a couple of cars before, and ive heard manifolds....Headers are louder than manifolds, the exact reason..im not sure of but they were louder. Also to the op, have you checked your local sound level laws to make sure you wont get a ticket for this?

andrewk · Joined: 18 May 2005 Posts: 1228 Location: Ames, IA

91parkave wrote:

anyways.....back to the header comment....Ive installed long tubes on a couple of cars before, and ive heard manifolds....Headers are louder than manifolds, the exact reason..im not sure of but they were louder.

This might be a good topic for another thread- I'll start it up here

91parkave wrote: Also to the op, have you checked your local sound level laws to make sure you wont get a ticket for this?

aron115 wrote: well the law for noise for music is 100db around here and my subs do 125db in the car so yeah im already breaking the law.

I don't think he cares if he is.

andrewk · Joined: 18 May 2005 Posts: 1228 Location: Ames, IA

Hi all-

This thread really took off-

88Coupe wrote:
In the '50s, luxury car manufacturers started using resonators to finish what the mufflers did not.

I did not realize that they went back that far, that is sorta neat.

The resonators that I have seen on cars (Mostly late-model FWD stuff) have all been installed before the muffler. The way I read the above quote is that they used to install them after the muffler? Does it matter or affect the exhaust to have it one way or the other?

88Coupe wrote: Number of cylinders has little, if anything, to do with it.

Total displacement, compression, and cam timing, have a lot to do with it.

How do they relate to each other? For instance, a typical chain saw has about 13:1 compression, but only about 25cc displacement. They'll deafen you. A lawnmower, with 900cc's of displacement, roughly 11:1 compression is not nearly as loud. That would lead me to believe the larger the engine, the quieter the exhaust, but I know that there are large displacement engines that are very loud-

I am certain there is more to it than that- could you explain?

andrewk · Joined: 18 May 2005 Posts: 1228 Location: Ames, IA

oldsguy98 wrote:
Flowmaster uses Helmholtz resonators. and in a nutshell its like blowing over a coke bottle. different amounts of liquid produce different sounds.

When did Flowmaster start putting liquid in their mufflers? Can you tune them by adding or removing fluid to these resonators?

91parkave · Joined: 29 May 2007 Posts: 516

I dont think flowmaster ever used liquid to tune, more or less The amount of "wave" guides in the chambers is what i always thought they used to tune the sound. However the resonance produced from the flowmasters is quite irritating especially on highway trips

aron115 · Joined: 27 Nov 2007 Posts: 33

well on my 85 the resonator was after the muffler which i thought was pretty weird. i always thought it would be before.

would it be hard if they put water in there to keep it in there?

andrewk · Joined: 18 May 2005 Posts: 1228 Location: Ames, IA

aron115 wrote: would it be hard if they put water in there to keep it in there?

That was my point. Sometimes my humor doesn't work I guess.

It was my subtle attempt to get the poster of the information to clarify his statement, so I didn't have to, but he hasn't been back to post yet. Oh well.

While a Helmholtz resonator traditionally uses fluid to change the "pitch" of the sound coming off of it, Flowmaster mufflers do not. It would be more accurate, in the context of this thread, to say that different sized chambers make different sounds, rather than paraphrase wikipedia into this thread, where it doesn't make much sense without further explanation, which was not provided at the time.

The chambers in a Flowmaster muffler work off the principle of a Helmholtz resonator, they do not operate like them in the traditional sense.

It may be semantics, but I believe it is a point worth making. If the mufflers were just a Helmholtz resonator, and operated as such, they would be much more efficient than they are.

aron115 · Joined: 27 Nov 2007 Posts: 33

yeah i know it was your point. i brought it up again because i thought it was a valid question and i really wanted to know the answer to. my resonator had water in it. but i dont think it was put there.

88 Coupe

aron115 wrote: ........ probally plugged up a tad or something ........
Good guess.

Norm