Weld ins vs. Cat back,

[STANGateURlilSS]

It has cats bro... maybe by the end of christmas i'll get a UPR O/R

now that will be loud.. but then again not too loud your only running 2.5" pipe..

as for performance.. running open pipe i would say your losing torque.. but if you want noise you got it

 

[Gunmetal5oh]

as for performance.. running open pipe i would say your losing torque.. but if you want noise you got it

Exactly. That's why I made the suggestion he buy a slow import and stick a coffee can on it hahahahahahaha

 

[ponysarepretty]

Exactly. That's why I made the suggestion he buy a slow import and stick a coffee can on it hahahahahahaha

How is cutting out the mufflers drastically different from getting an O/R X pipe? Both reduce restricitons in the exhaust?

 

[Gunmetal5oh]

Lots of people have x-pipes but not without mufflers. It was just my impression that you are trying to rice out a mustang.

 

[ponysarepretty]

Lots of people have x-pipes but not without mufflers. It was just my impression that you are trying to rice out a mustang.

Hardly... either I will put the mufflers on (which i have two of which sitting in my garage) and get an X pipe or just leave it as it is and buy a throttle body and a plenum

 

[ponysarepretty]

And how the hell is that rice at all? What, just because straight pipes aren't flowmasters they are therefore something a rice car would have? Or is it because few people have straight pipes?

Would someone care to define rice?

 

[Gunmetal5oh]

Your car is LOUDER but not FASTER. That's RICE-LIKE. Import guys always make their cars louder instead of faster by sticking on an exhaust tip.

 

[ponysarepretty]

Your car is LOUDER but not FASTER. That's RICE-LIKE. Import guys always make their cars louder instead of faster by sticking on an exhaust tip.

So your saying that I gained less power than the average guy who welded in some Flowmaster 40s?

 

[Gunmetal5oh]

I don't know about the 40 series in particular, but very likely so if compared to high flow mufflers. You want backpressure for torque down low and very little restriction when wide open.

 

[ponysarepretty]

I don't know about the 40 series in particular, but very likely so if compared to high flow mufflers. You want backpressure for torque down low and very little restriction when wide open.

So an X pipe would be detrimental because you lose too much backpressure?

Or is the X pipe backpressure something special and something that you don't need. because from what i gather the cats are bigger bottle necks than the mufflers are?

 

[SamMan]

Whatever man. Cutting out the mufflers is redneck not rice.

Besides like he said hes running what ... 4 cats right now?
Mine had four before I put in the Hpipe and some crappy little Forza mufflers which was basiclly like not having any mufflers at all. It sounded great then but once I took out the cats the car sounded like a 78 Ford pickup with rebel flag stickers on the bumper.

I got some weldin Flows yesterday and it sounds AWESOME. I also regained some of my low end torque back which brought a good balance to the combined exhaust mods.

 

[Gunmetal5oh]

pony, dont try to be smart. An X pipe will equialize pressure and improve exhaust scavenging. Chopping off your mufflers will cut a lot of your bottom end power.
You probably think its faster because its louder, but put that thing on a dyno and you'll see.

Get yourself some low restriction mufflers that offer some back pressure at low RPM's and you'll GAIN power.

 

[ponysarepretty]

pony, dont try to be smart. An X pipe will equialize pressure and improve exhaust scavenging. Chopping off your mufflers will cut a lot of your bottom end power.
You probably think its faster because its louder, but put that thing on a dyno and you'll see.

Get yourself some low restriction mufflers that offer some back pressure at low RPM's and you'll GAIN power.

What does equalizing pressure have to do with backpressure? So you are saying that the scavenging abilities of an X pipe counterbalances any lose backpressure?

I don't think its faster, but no restriction should be good for high RPM shouldn't it? Then wouldn't the car make HP regardless? You would lose some power in the low RPM and gain some in the high RPM?

And why don't cats provide adequate backpressure?

I'm not trying to be a bitch, i really want to know.

 

[Gunmetal5oh]

Ok, you need some level of back pressure to make torque down low. What an X or H pipe does is tie both exhaust pipes together, this equalizes pressure and improves scavenging. Having an X pipe will boost horsepower, but it is not a replacement for a good set of mufflers.
What you want to do is compare flow data on different mufflers and find something in your price range. High flow mufflers will give you back pressure down low and they won't hurt your top end. And remember just because a muffler is loud does not mean it has good flow characteristics. Many flowmaster mufflers don't flow well for engines producing 300-400HP.

 

[timeless2]

What does equalizing pressure have to do with backpressure? So you are saying that the scavenging abilities of an X pipe counterbalances any lose backpressure?

I don't think its faster, but no restriction should be good for high RPM shouldn't it? Then wouldn't the car make HP regardless? You would lose some power in the low RPM and gain some in the high RPM?

And why don't cats provide adequate backpressure?

I'm not trying to be a bitch, i really want to know.

Aerodynamics and the underlying concepts of flight will help you see why pressure equalization is necessary for maximum airflow. Do a web search on flight, aerodynamics, pressure balancing, etc.

 

[helty]

pick up the November and December issues of MMFF mag. there are two really good articles about exhaust flow and sound, very in depth. i believe they were written by the engineer that designs ford's exhaust systems. lots of good info. why an X is better (power wise) than an H and why they sound different, how and why the different types of mufflers and resonators make the sounds they do....good stuff.

also did you know the exhaust that comes stock on a 5-speed is different than that of an auto? interesting.

 

[deftsound]

pony, dont try to be smart. An X pipe will equialize pressure and improve exhaust scavenging. Chopping off your mufflers will cut a lot of your bottom end power.
You probably think its faster because its louder, but put that thing on a dyno and you'll see.

Get yourself some low restriction mufflers that offer some back pressure at low RPM's and you'll GAIN power.

sorry to bring up an old thread but this is retarded. Your not going to lose a significant amount of backpressure from taking out mufflers when you still got a catted h pipe (4 cats). I have an offroad h pipe and dynomax ultra flo mufflers and i gurantee you i have less backpressure then he does and i can honestly say i didnt notice any loss of low end torque. Yes i obvoiusly lost some (minimal) but what you lose down low you gain up top... And as far as flowmasters, ive heard you actually lose power when you put those on, and id definately say that cutting mufflers out with a 4 catted h pipe is going to give you gains as long as you keep those cats. You probably lose more backpresure from taking the cats out than taking the mufflers off.

 

[Gunmetal5oh]

What you notice and what you lose are two different things. When you make something louder to some people it may seem faster. He's running straight pipe with cats.. which are not a substitute for real mufflers.