I'm planning on changing my exhaust But want dual exhaust. I've searched for this topic and found afew enters on other posts. Has anyone installed dual exhaust? What kind of exhaust did you use? Any problems?

Well a guy from my local X club has a dual exhaust set up which is sweet...He's running a Flowmaster either 50 or 40 series muffler with some pipping that he had done at a local exhaust place....

I love his set up and is probably what I'm gonna run when I have the extra cash.

But if I was you I'd look into it first cause I'm not sure if it can be done if have a stock trailer hitch on your X.....

As soon as I get paid on Friday i'm going down and having a custom set put on.

That would be Stormy\'s X .

I don't think you can install one with the spare in the stock location either, unless you have the 2 pipes exit on the same side. Even then its tight.

i'm going to locate the spare on the rack and have the pipes str8 out

Can any of you tell me if that dual exhaust setup is a TRUE dual exhaust? That is, there are 3 cylinders venting to each port...

So many punk-ass rice boys split the down pipe with a "Y" adapter of some sort and call it "dual exhaust." I guess it looks cool, but its a lot of $$$ for no horsepower gain whatsoever.

Mine was cheap Look at it as a crossover, using a single muffler. Mine also exit out the one side--I like my spare where it is. When your friends own muffler shops why not?

is there any performance loss/gain by doing a dual instead of a single exit exhaust?

On mine i'm going to have a true duel set up, waiting for the mufflers to get in and need to decide if i want different cats

Guess I'm a punk-ass rice boy...

Holy shit, yes. This is a rather elementary observation actually... If you try to cram the exhaust from 6 cylinders into one pipe, the exhaust flow rate is limited to the smallest aperture that's found along that pipe. If you branch the pipe into two or 50 other "branches," the rate of the out-flow doesn't change. Think of your exhuast as a "crazy straw." If you plug a "Y" adapter into the end and connect another straw, you still wouldn't be able to blow fluid out of it any faster...

This is why most V8 engines vent their exhaust into a TRUE dual exhaust system, 4 cylinders on a side.

If you really want to be technical, the "dual" exhaust you guys are talking about actually reduces performance to a very minimal degree because you're carrying the added weight of more pipe, and depending on how smoothly the pipes are bent and welded, you may be adding more back-pressure to the whole system (you have blow harder to get fluid through the straw...)

I guess it "looks cool" though. :rolleyes:

The only way to get increased performance out of your exhaust is to toss your catalytic converter and use wider diameter pipe to vent the exhaust more freely and faster (less pressure).

so your saying that exhaust on a dual setup is restrictive because of the smaller diameter pipes? I would disagree by saying that the flow is the same through those two pipes as it is through one bigger one that equals the same diameter over all. I have a 440 wedge that I suppose you would not consider a "true" dual exhaust because it has the crossover :rolleyes: I used the same idea with the Xterra exhaust I did, except I used the muffler *as* the crossover point instead of using two mufflers with the crossover upstream. If you cut the "Y" at it's widest point, you have about 3", from there a Magnaflow muffler with siamesed 1.75" pipe out the back.

It sounds good (not like a flatulent elephant) and helped with driveability and towing as near as I can tell without getting it dynoed. Whatever you want to call it, it is a custom exhaust and it works better than the stock system I would add that "true" dual setups often don't sound all that good and with the addition of a crossover you get a much better tone.

Where did I say that? I never said that. I'm talking about the existing pipes. What I said was, ANY exhaust system only flows as freely as the smallest aperture in the system. In other words, if you have a 1.5" diameter section of pipe 3 feet aft of your oxygen sensor, it doesn't matter WHAT sort of "Y" adapter you have afterwards, you're not getting any higher flow rate or performance boost because you're still restricted by that length of 1.5" pipe.

If you have a 56k modem, upgrading your computer won't get you faster download times unless you upgrade your modem as well. The only way to get a true performance hit with "dual exhaust" is to vent 3 cyls out one header, and the other 3 out of another header... then vent both down their own pipes.

Use my crazy straw example, insert a 1:2 adapter on the end and plug another sraw into it. You still have to blow through a bunch of 1/4" pipe before your air comes out of your "dual straw exhaust." Put 6 straws on it, you still can't exhale any faster.

In your case, you'd actually have better less restrictive flow if you cut the "Y" off and left the existing pipe hanging. the more bends and turns and restriction (muffler, cat) that the exhaust air has to travel through, the worse your performance will be.

I'm sure it looks good, I'm sure it sounds nice, and I'm dead sure your car or truck is not any faster.

I didn't ad the Y, it came from the factory. I would have recieved the same results going 3" in/out, but the muffler was free, and my friend was feeling creative so I got two pipes. It's a lot less restrictive. Power gains? Maybe 1-2 hp, same as most exhaust mods on imports. If I had to pay a lot for it, I would have the stock setup still installed. I'll see if I can get a shot of the "Y" portion for you...

The 440 on the other hand benefitted greatly with the dual exhaust

Most exhaust mods on imports replace everything from the headers to the tailpipe with fatter pipe. This will give you a slight performance gain. Simply adding an aditional muffler to your stock pipe (and the pipe to feed it) does nothing.

I can't tell from your picture if you kept the stock headers and downpipe or not. If you did, you will have ZERO performance gain, no matter how pretty your undercarriage is.

Why is this so hard to understand? You can put the prettiest mandrel bent pipe the world on the back of the most expensive hi-flow muffler you can buy, but you won't get any performance gain unless you add thicker pipe or move to true dual exhaust.

My original point was, if you tail off the stock pipe in front of the muffler just to add another muffler and tailpipe, you've done nothing but spend a bunch of time and money to make something look like something you don't really have. That point is still valid. You haven't impressed me with your "1-in 2-out muffler". If you want to impress me, show me a picture of the 6-into-1 ceramic large diameter hi-flow header, and the large diamater down pipe, hi-flow cat, and high flow muffler. If you have 2 inches of stock pipe left in your truck, your exhaust STILL flows at the same rate it did before... ie, no performance gain.

Again, "dual exhaust" means you have TWO headers, TWO down pipe, TWO cats, TWO feed pipes, TWO mufflers, and TWO tailpipes. Anything else is NOT "dual exhaust" to the purist.

Stock pipe anywhere in your system is the weakest link in the chain. Replace ALL pipe with larger diameter pipe and you might see a performance bump. Replace cat and muffler with hi-flow performance units and things get better still. But if you cut the pipe and add shit to it, no matter who your friend is or how expensive it may be, and you get nothing but an image.

I think the guy cut the exhaust @ the Y & added 3" pipe from that point to the muffler (this is what he stated & what I can see from his picture at least). This combined with the 2 pipes out of the muffler, there is better flow in the overall system (because the stock setup reduces to sub-3" piping between the Y and the muffler).
Also, "performance" is subjective; I've heard from several sources that too little backpressure hurts low-end torque, which equates to decreased performance for most concerned here. So, even though his system does allow for easier flow than stock, my belief is that he lost what I consider to be performance.
And finally, the smallest aperture does not determine the flow rate. This is the same with water running through pipes & electrons traveling through wires: the resistance of the medium increases with increasing length for a given x-sectional surface area (for example, that's why for a longer power lead to a car battery, you need thicker gage wire (i.e. larger diameter electron "pipe" to handle the SAME current load). How does this relate? If you have a 10 foot long pipe having a 2" diameter over the entire length, the gas flow is MUCH LESS than for a 10 foot long pipe having a 4" diameter MOST of the length but with a small 2" aperture placed somewhere along the way.

EDIT: when I say "more flow" or "better flow", I don't mean more gas is exiting, just that it is "easier" for the gas to exit (i.e. less of a pressure differential between the entrance & exit of the tube (or, less backpressure).

How can you not get gains getting rid of the stock diameter and muffler? There are two stock down pipes going into a Y and then out

Sorry dude, no cats on this one (72)...dumbass. Show me your system when it gets installed, until then Aftermarket exhaust will give you gains over stock, you must be cranky or something, relaxxxxx.

Added:
Not to start anything (or continue it), but why is it that when folks ask about this stuff people that haven't done it always feel the need to chime in. I put that set up in, I'm happy with it, and I had no loss of torque or any other adverse effects. It's all good as far as I'm concerned. If you are around you are more than welcome to take it for a spin and see for yourself. I'll even let you pull the trailer for a while (5k#+). That's all I've got for yah

I thought so, too, but then read this:

White Paper on Exhausts by Dinan

First thing: I'm no exhaust expert. That said, a quick internet search reveals a multitude of articles, etc... that basically say the same thing: bigger diameter is better...to a certain extent; then, at some point (depending on engine size & volume of gases generated that need expulsion), too large a pipe causes decreased low rpm performance (I even read one blurb about large diameter causing the gases to cool down faster, thus increasing in density & therefore requiring more work to expel...this work has to be done from the engine (I'm not sure whether or not to believe that one, though).

In the end, nearly everything is complicated if you look at it close enough & certainly there is no single diameter that is best for all engines; it seems to be very engine specific as to what exactly is the optimal & it seems quite clear that optimal is in fact a matter of where you want your power.
Links:
Link 1
Link 2
Link 3
In addition, & quite coincidentally, I happened to meet & speak to an owner/operator of a long-time muffler shop & he indicated to me that for my engine size, 2.25" would be the right diameter for increasing flow but keeping power gains at a reasonable point on the RPM curve; his opinion meant a lot to me because he had a nice intake/exhaust system on his trail-ready Jeep & he seemed very familiar with the type of performance best suited for offroad vehicles. I'm not saying I'd trust the guy with my life of course 'cause I just met him, but it's easier to believe someone talking to you face to face in his own muffler shop than a web page....

Charlie, I'm not the dumbass, I'm just tired of making my point to pinhead punks like you who won't listen. I have a LOT of experience with performance exhaust systems on racing cars, I'm not stupid enough to fuck around with the time and money it would take to do it on a truck.

for the third time (since you're obviously dense):

-Replacement of stock muffler AND stock diameter = a slight performance gain.

-Venting all six cylinders through one pipe at any time during the flow means you do NOT have dual exhuast.

-Having two tailpipes sticking out of the back of your truck does NOT mean dual exhaust.

-Replacement of stock muffler with top of the line equipment means NOTHING if you leave everything in front of it stock.

This is what I've been saying the entire time, Ricefuck. You do what you want with your truck, I don't care... its your investment. I'm through wasting my time with you. I'm sure your system gives you a massive performance gain and an enormous hard-on, be sure to get some stickers on the side of your truck that say, "DUAL EXHAUST," the pubescent rice boys holding their little peckers will be quite impressed.

Thanks for the feedback, I still think you should relax