Purple Hayz

Two prefaces: First, I'm not terribly bothered by the exposed mufflers, so hold back the Second, I have little idea what the impacts on performance and sound decibles will be . That's why I'm floating this topic to all of you

So here goes.

Pros:

-minimal cost (in exhaust work, anyway.....hearing loss bills notwithstanding B) )
-pickup a few ponies (I'm thinking about 5)
-shed some weight
-clean up the view from the rear
-get to hear that killer muscle car sound everytime you fire it up


Cons:

-HAVE to hear that killer muscle car sound everytime you fire it up
-may alienate friends, neighbors, loved ones
-may go deaf (though I imagine the 05 is leagues above the SN95 in noise isolation and sound deadening, so maybe it will be tolerable from inside the car with the windows up )

I was also wondering if the huge decrease in back pressure could negatively effect the power output (isn't this the same argument against oversized exhaust systems?)


So that's my idea for the day. What's scary is that I'm actually half considering it. If that blown four-banger in the NEON (sorry....SRT-4) can pull it off (no mufflers), why can't our honkin 4.6 liter V8? Besides, having listened to that V10 Boss Mustang video about a hundred times, I must admit I find that deep, booming, snap-crackle-pop sound to be positively wicked!

Shea

Absolutely the lack of backpressure would affect it. You need to study up on exhaust design before you attempt something which would alter it as severely as removing mufflers.

Ever wonder why equal length headers are so popular? Read up on exhaust pulses. I'm not saying that you can't overcome this issue through tuning, but it would take a LOT of tuning. A better way would be to remove the cats and keep the mufflers. The cats are your biggest restriction, and also your most heavy exhaust components, and, for that matter, they make your gas mileage go down as well.

dallasw77

I agree with Shea, besides I'm not sure if it will sound that great w/o the mufflers....need more engine to make it sound good

kevinb120

don't do it.

crawFord Mustang

Depending on your locality. There will be two issues, unless you know a slimy mechanic.

Emissions checks
and
State Inspection

Won't pass either.

Sure, people often do it, but sooner or later they will be fined.

Oh, and another:

Pass a cop with it that loud, he's sure to stop you. Then, I will refer back to the previous two issues.

Galaxie

you will get plenty of noise violation tickets :cop2: :nono:

dyno tests have shown some engines actually LOSE power with no mufflers

Sounds fun for a while.. but the first 100mile trip you make with no mufflers will be your last.

Boomer

A 4banger SRT4 is way samller than a 281 ci ... 4.6 3v v8
Also it has RESONATORS which make a difference..its not open pipe from the manifold on that car.

Mufflers no, but resonators yes.

Don't fool yourself...

StevenJ

What about louder mufflers? Like um...... Flowmasters for example? They tend to sound good. Something like that is legal right? I mean, I'd like to hear the car but I can understand the need to tone it down a bit. This is funny actually. I was riding with my aunt. She was driving her mom's 03' Malibu. I had my cousin, her son, on my lap, and my uncle was up front. We were bringing a tv over to my grandma's. On the way, we passed this guy that had a early 80's Nova with rust that obviously just had a Chevy big block crate motor dropped in it. It was loud. I mean, you could hear it comming from miles away. I loved the way it sounded but my aunt and uncle, who represent the average joes, found it way too loud and couldn't stand it. So I understand the need for a muffler. Just not quiet ones. I think a middle ground can be found.

FinlayZJ

Very true. We did a pneumatic muffler design for my senior engineering project at Clemson in fall of 03. There is a ton of factors to consider when changing your muffler. Most engines need the back pressure to create the maximum hp numbers you will want. Just cutting off the muffler will make it loud, but more than likely, slower. The trick is to get the sound through, with the right amount of pressure. I'll pay the $$$ to get a real muffler to put some rumble under my 05.

dallasw77

There is a point where you have enough horsepower where mufflers will hamper peformance, no matter what type of muffler (hence that is why you see no mufflers in NASCAR/NHRA). But I don't say that because the pros don't run them, it is proven on dynos that higher horsepower engines get hampered by mufflers. Each engine is different and only tuning on a dyno will find you where that point is.

Purple Hayz

I have a bad feeling about this :jedi:


Yikes, never even considered the noise violation aspect. You are right, it wouldn't even be worth it....Flomasters it is, then

Oh well, it was a fun (if completely unrealistic) idea...

dallasw77

hehe hey it's fun doing no mufflers in your garage or car show for my 68 camaro! 555 cubic inches sounds really good when it is not muffled up!!! Shoot even with my 4" flowmasters on there cops look at me like they want to pull me over!!! Just lucky I haven't found the uptight by the rules cop yet.......

Arboc

with no mufflers it will sound like a burned out chevy 305

plus as mentioned u will loose backpressure and therefore power

MedVader

Wrong. On the backpressure arguement.

Exhaust flow is the real determinant. People moving up to larger pipes tend to lose exhaust velocity and thus actually reducing flow and hp. Or they may reduce flow at low RPM and pick up flow at high RPM. Given identical pipes (which he'll have just cutting off the muffler) he will reduce backpressure(restriction) WITHOUT reducing exhaust velocity at any RPM. And he'll make more power.

Equal length and TRi-Y headers are good because they scavenge exhaust ie. increase exhaust velocity.

The reason an SRT-4 doesn't need a real muffler is that thingy called a turbo. It makes a great muffler too.

Dan

You crazy I seriously thought this post would be about going with an aftermarket set of mufflers which are less obvious........but removing the mufflers all together, man you must REALLY hate those things....and your ear drums.

MR325iT

MedVader is right on. The backpressure argument isn't entirely correct.

http://www.uucmotorwerks.com/html_product/...etorquemyth.htm

Boomer

Just get an O-Pipe and be done with it

FinlayZJ

Ok, so you're going to tell me that a muffler doesn't create any friction loss? Given two identical 3" diameter equal length pipes, one with a muffler, one without, the exit velocity will be the same? Apparently the laws of physics fail to exist in the exhaust system of you car.

It takes pressure (a force) to move the exhaust through the pipes. The walls of the pipes create friction and how much exhaust (in CFM, cubic feet per minute) can be pushed through your pipes is a function of pipe diameter, material, length, gas density, and the amount of force it's getting pushed or pulled with. One can also consider the change in height from where it exits the block, to where it leaves the muffler. However, gases are so light that it's basically worthless. Gases are very particular about "minor" losses such as change in direction and objects that interfere with the laminar flow, such as A MUFFLER. I haven't seen the inside of the new stangs muffler, but it is usually numerous chamber and baffles, that force the gas to change direction a few times. This in turn creates friction, slowing down the speed of the air and reducing the EXIT VELOCITY. The reduced exit velocity makes the amount of gas trapped in the pipes increase, therefore creating the flow leaving the block to be slowed. This is what some call "back pressure." And for engines, larger diameter pipes usually shift the the max hp and torque numbers up the powerband.

kevinb120

BASSANI

JeffreyDJ

Borla

But yeah, deleting would be a bad idea. Friend at work has them off his 98 Corbra. He claims to like it, but may just not want to put them back on (he bought it with it off). Sounds llike pooey though, IMO.

Yes, its loud, but the quality of tone and sound with a GOOD muffler will be much nicer.