I'm considering cutting off the muffler, and just welding a piece of straight pipe where the muffler used to be. Does anyone have any idea of how this would sound?

Like crap. :)

That might be a bad idea. You might lose some back pressure. But i am not 100% sure on that but like he said it will sound bad most likely...

By all means, get the sawsall out and chop it off! It will sound like crap, but what the heck.

In fact, as long as you have the sawsall out, chop as much weight off the car as you can. That will make it faster for sure. When you get the car down to just 1 seat and the chassis, the performance will stun you. Of course you better live in Phoenix, otherwise you will get wet when it rains.

And if you want backpressure, just get out the vise grips, and squeeze the pipe down till the car runs the best.

Someday you folks will come to the realization that the back pressure thing is a myth, but until then, feel free to experiment.

Why the hell would companies make headers...and free flow cats, and free flow mufflers? Do ya think NASCAR builders want back pressure? Or NHRA Pro Stock cars? Or Top Fuel cars...or Funny Cars? Or Comp Eliminator cars? Or even Stockers?

Read the stuff that matters, educate yourself. It's all out there.

RS

what the hell would be the point? Are you simply going for the sound? . . . have fun buddy

Hey, it wasn't my idea now! My friend wants to do it, he chopped the mufflers off his M3 and it sounds GOOD.

I'm considering cutting off the muffler, and just welding a piece of straight pipe where the muffler used to be. Does anyone have any idea of how this would sound?
First of all, the highest restrictive part is the header. Second one is the muffler, good for 8 to 10 whp on the Cobalt SS / SC. If you didn't put any muffler at all, it won't be better for HP than replacing it by (for say) a straight trough Magnaflow 2,5". All it will do it will make a LOT of noise for nothing more. Another thing: "Loosing backpressure" is misunderstand by some people. Tha main goal of tuning is to have the highest CFM possible, and going too large for the catback portion won't gain more, but will NOT loose more anyway. A minimum of backpressure is good only in the primaries of headers, not at the muffler.

http://www.popularhotrodding.com/enginemasters/articles/hardcore/0505em_exh/

I work for a Dodge dealership in Ohio, and it has come to my attention that all of our srt4s that come in for oil changes are missing their mufflers. Its a strange sight, but these kids swear by this theory. And yes 9 out of 10 srt4 owners are age 16-20, at least in my area. PUNKS!!!! hahaha

I work for a Dodge dealership in Ohio, and it has come to my attention that all of our srt4s that come in for oil changes are missing their mufflers. Its a strange sight, but these kids swear by this theory. And yes 9 out of 10 srt4 owners are age 16-20, at least in my area. PUNKS!!!! hahaha

If i remember correctly SRT-4's do not have mufflers at all.... i could be wrong... :confused:

I personally did that just to see what it was like. the exhuast note sounds too much like rice AND WAY TOO LOUD!!! so loud you have to crank the stereo up several notches just to hear it and your cant even hear the s/c whine. I also lost performance that way. then I put the 2.5" staight thru magnaflow xl performance series and gained the performance back and it still sounds good(louder than stock) and I can still hear the s/c whine.

That is correct, SRT4's dont have mufflers.

Your right your right. They have dual resonators. It seems that the thing to do is to chop from resonators back.

On the srt, the turbo acts as the muffler.
As for backpressure. The correct term is scavenging effect. And it is not so much pressure against the engine compression as it is getting the exhaust gas to flow so freely and smoothly it almost begins to draw itself out. Like drafting in NASCAR racing. Removing your muffler may help create this effect, but it is obviously unanimous, it will sound terrible.

does it work the same way for a supercharged as opposed to turboed?

Your right your right. They have dual resonators. It seems that the thing to do is to chop from resonators back.

Yeah that is what i thought.

Someday you folks will come to the realization that the back pressure thing is a myth, but until then, feel free to experiment.

Why the hell would companies make headers...and free flow cats, and free flow mufflers? Do ya think NASCAR builders want back pressure? Or NHRA Pro Stock cars? Or Top Fuel cars...or Funny Cars? Or Comp Eliminator cars? Or even Stockers?

Read the stuff that matters, educate yourself. It's all out there.

RS

Sorry, but it matters for street cars. When you're running a cam that idles at like 2000rpm then yeah, it doesn't matter. It all has to do with valve duration and overlap. Say your duration is 240 with a lobe seperation of 110, you're gonna care a lot less about backpressure... your idle will also be lumpier than bad oatmeal. Hell, bracket racers and the guys you're talking about probably run durations over 300 with a seperation round 108, they also run big V8s to 8000rpm. With the SS, I'd guess that it might be running 220 duration 115 seperation angle? (can't find specs) Smaller seperation angle is more aggressive, but SCs like it to be a bit wider... since you're forcing air in gotta be a bit more pickey about how long all of the valves are open at the same time.

sc is not affected by chopping the muffler off but the ecu will pick up on the muffler missing and try to compensate eventually youd burn the o2 sensors and the cat with no muff at all even a fart can has some baffles in it

Ya last time i checked.. a turbo creates enough backpressure.

You don't need backpreasure for scavenging on a supercharged car. Thats already been discussed a while back. So you guys need to open up the exhaust as best as you can.

The TOGs with a 3" downpipe/catback is the best idea. I would definetely throw some type of flow-through muffler in there or atleast a resonator.

And valve overlap is bad for turbo/supercharged cars. To much overlap, and boosted air is waisted out of the exhaust valves, so you get alot less boost. Sounds cool with all that lope, just isn't very useful. NA cars need that lope.

I'm new and I don't want to come off as a ass but by chopping off the muffler the ecu will maybe only notice an increase in the amount of air passing throught the engine and no it will not burn out o2 sensors and cats. And before you ask how i would know, I work at a GM dealer as a tech and deal with this all the time.. sorry if i offend anyone

I work for a Dodge dealership in Ohio, and it has come to my attention that all of our srt4s that come in for oil changes are missing their mufflers. Its a strange sight, but these kids swear by this theory. And yes 9 out of 10 srt4 owners are age 16-20, at least in my area. PUNKS!!!! hahaha

I really hope your kidding. Other wise you sir are a dumb ass! :rolleyes:

oh really i am wrong then. do tell

oh really i am wrong then. do tell

Are you asking me? Because my post wasn't really about yours. I was refering the srt's as they don't have mufflers. Witch I just noticed some else posted already lol.

What you said make's sense to me. I don't see removeing the muffle affecting the o2 sensors in anyway. In fact I don't think it will hurt anything more than your ears.

How am I a dumbass?!? I fixed my mistake. If you would have read carefully, you would have seen that.

And if you had read closely you would have noticed I admitted to not reading the hole thread and that it had been covered already.

Sorry I didn't see there was a second page the 1st time I read it.

I still say your a dumb ass as you work at dodge and still needed correcting. And you own a wrx and don't know how much diff exhaust makes on a turbo car. But, I guess you should expect me to say that as I am a "punk" because I own a srt, the fastest car evar.

Spell Check you Prick!!!! I am a new WRX owner, and haven't fully traveled all there is to know about the car universe. If I am a dumb ass for that reason then let it be so. You sir are a typical SRT owner, defensive as all get out, and as smart as you are handsome. Have a great day!!

Wow there's spell check on here? I wish I knew that. lol

And I guess I am a typical prick of a neon owner, as most of us would determine you don't know shit after your exhaust comment. And then you refer to us as being "punks" tends to upset us just a little.

Your just mad you can't beat my neon. It's ok, I understand.

Now lets get back on topic, I say buy a exhaust don't chop it off. Or is it possable to just unbolt it before you start cutting shit? See if it sounds ok, and just put it back on when you get inspection tickets.

Wow! Just as I figured. Right over your head!

Wow you got me there. Good job!

All I got out of your post was you consider me a punk, prick, defensive, and handsome as I'm sure you weren't implying that I'm dumb and ugly. Witch part did I miss?

And I'll add you don't need to know everything there is to know about the car universe as you put it. No one knows it all. But as a dodge employee you should at least make a attempt to know the cars they sell. And it probably isn't the best business practice to refer to your customers as punks.

Ok.........

FYI Personally my base coupe sounds badass without my muffler. I mean its really really loud, but its not weed wacky at all. Its a very low tone to tell you the truth. But like I said its very loud but thats really only when you are accelerating. It depends if you like your neighbors. If you do, keep it on. If you don't by all means cut that biotch off. As far as ECU, maybe the base coupe runs a simple ECU, because I have had no problems.

And it probably depends on your local cops. I had a wrx with a 3" turbo back that was loud as hell. I got three inspection tickets in a could of months. Then changed my setup becuase it was just to much trouble. If you can get away with it go for it