Im sure this has been thought up before, has anyone found out if its possible or not? I figured you could start where the ypipe ends (two pipes coming down after the 02s) and those would branch off into their own pipes. This would eliminate the cat though and would require an 02 simulator. But i figure, the piping would be smaller than 2.5" and they could run down the stock path right next to eachother, then split after the axle. Any thoughts?

 

CustomMaxima has a set for 4th gen Maximas. Here ya go!

 

Is that true dual exhaust? the answer is no.

 

u'd be getting more flow, but thats not always the best thing, u could really lose some torque. ur also adding wieght. and it may sound really funny, i know SHO's that run true duals sound really raspy due to the fact that the two pipes arent the same lenght, this would be true of any transverse mounted V engine. , but besides those points, i love to see someone do it, u never know what could happen, props for doing ur own thing, best of luck nad keep us posted

 

I thought about this a while ago...but if you're talking about a TRUE dual exhaust, why would you use a y pipe at all? I think the best setup would be 2 separate pipes coming from the exhaust manifolds with an X-pipe instead of a cat. I guess the advantage of this would be that you can use two 2" exhausts instead of 2.5"...which could give you better velocity. But it probably won't sound all that nice.
Anyone have more knowledge on this???

 

You wouldn't need an o2 simulator. There is very little advantage to be had in true dual. Let me tell you what I'm doing. Beginning at the y-pipe I'm running 2.5"(There will be no cat). Just after the y joint will be the o2. Then a resonator followed quickly by a muffler. Then I'm going to do a downward bend to point the exhaust toward the ground. This will add to the quality of the sound and the body of the car will do a lot to eliminate raspiness. Done! It is the lightest, least restrictive, quietest exhaust that can be made for these cars.

 

I have the same plan for mine. Only thing I was worried about is fumes during slow traffic/stop lights.

 

Fumes shumes... Suck it up. LOL. Actually, this is a good point but I don't have to worry cause I never drive in traffic.

 

So what advantages would this have? Anyone have anyideas? I know it would sound cool. Maybe it would help a F/I setup. But you have to have a stroker if n/a for it to really do something, am I right or wrong. But I still think the notes that thing would make would be like a symphany

 

everything is fake

 

The thing is, I believe that the name of the game is to improve performance by modifying the exhaust system. That's what happens with many of the aftermarket kits (we all know the various brands available). Fake duals do not accomplish that, most likely they restrict the exhaust even more than stock. So without engineering, your proposal would likely restrict the exhaust even more so than a fake dual system. Is all of this just for a look? When you really get into it, a V6 motor lacks secondary balance, so why do all this for no performance gains? BMW doesn't seem to worry about it with their I6 which would make no sense, nor does Lexus (on the IS300). Well, that's not completely true as the GS300 has duals......I remember before this fake dual craze, people were mounting a kit designed for a 95-96 on their 97-99's and having it not fit properly under the rear bumper, yet they did it anyway because they wanted the newer kit. It just occurs to me that at any given point in time, people want to do things to be different, regardless of the results. But that's human nature, I guess. Like when I was in Stockholm, I saw several blonde girls who had dyed their hair black, so they weren't like everyone else. The opposite of what girls do here.

 

Once I graduate and become a successful Chemical Engineer I'll design a power producing, good sounding true dual exhaust system for the 4th gen.

 

I don't thing that pointing your exhuast down will quiet it down. In fact the height only being 8 inches is going to create a resonation effect an will actually increase the sound. It is the same principal as pointing a sub woofer to the wall or corner with a few inches of space. The bass almost doubles. And its not really clean bass either, just really loud.

 

Silly question, but what does being a Chemical Engineer have to do with anything?

I have a degree in Chemical Engineering, and other than a few classes about fluid dynamics and a little thermo, not much is applicable. Nothing that someone couldnt' learn on the internet.

And to BlueC, the other posters are right. How would it be a true dual setup if you've already merged them with the Y-Pipe? You would just be running 2 pipes where one would suffice since they've already merged. No power gains. And if you actually ran them off of each bank, I'd think gains would be minimal and your exhaust would sound like total crap. 3 cylinders per bank unmerged, not smooth.

Finally, I doubt you'd have the room. I have a 3" custom exhaust on my car for the turbo, and it's already pretty tight. Even if you ran 2" pipes, it wouldn't fit in the stock exhaust pathway and you'd have to drop it below the body for clearance.

 

If you read it again you'll notice that I said, "This will add to the quality of the sound and the body of the car will do a lot to eliminate raspiness." I did not say or mean to imply that pointing it at the ground will reduce the volume. Doing so will probably decrease the volume but it will make it deaper and less raspy. 8 inches? Try four.

All these fake setups add weight and look stupid on a Maxima. A true dual short and open pipe setup would free up power but would sound like a street car.

 

IMO, running a true dual on the Maxima would work and would make power. A perfect example is my G35 sedan. It has a Y-pipe which then turns into a single pipe. Borla and Stillen have both developed true dual systems for the G35 sedan and the gains are around 10-15whp. The G35 already has some decently big piping (2.5" ID) and to gain 10-15whp switching to a true dual is quite a nice gain. The downside is exhaust noise. It increases substanially and a lot of us G owners don't want our cars sounding ricey. It's too nice a car to be sounding like that.

Anywho, I had always thought about doing a true dual setup with 2.5" down pipes and then 2.3" pipes narrowing down 2.1" pipes near the beam. I would have used to balance pipes and then a Borla shorty muffler rotated 90 degrees and side by side where the stock muffler sits. The step down in pipe size helps increase exhaust velocity which is key to NA performance. The primary problem to mounting a true dual exhaust on a 4/5th gen is this......the freaking beam. It's totally in the way because it moves up and down and pivots side to side. With IRS, this isn't a problem because only the outside portions of the suspension move therefore you simply run the pipes under the differential because it doesn't move. The clearance between the stock exhaust pipe and beam is already really tight and I'm amazed people are able to stuff 3" pipes in the vicinity of the beam on lowered suspensions with absolutely no rattling or banging on chassis or beam when large bumps are encountered. Using my dual setup wouldn't clear the beam for normal daily use so I didn't research it anymore.

BTW, you CAN NOT run a pipe on the other side of the beam. There's no room. The pivot point of beam, the fuel filler pipe, gas tank, trailing, and some other components get in the way.

 

Y into cat w/ single in and dual outlets. About as true as a dual as you can reasonably do.

 

With that in mind, if you run both pipes through the passenger side of the beam, the drivers side of the tips will have a longer length unless you can somehow equalize both pipes. Thats if you do decide to have a pipe sticking out of both sides of the rear bumper. You could run the tubes ala' GTO style by having both tips on the same side. If you decide to run a main cat, its going to be really difficult to fit two cats down there side-by-side. An idea you could use is to run the cat for one pipe in the stock location while running a cat for the other pipe more downstream.

IMHO you should be fine as long as you don't run the same size as most aftermarket single-catback's. 1.75-2" should be fine unless you decide to go FI.

 

Just some Mass Transfer of gases through pipes. Of course you would need to know a little about the way flow effects power output. Once I know enough about the mechanics I'll try to make my own exhaust.