Dual exhaust questions

[Arthur]

Does anyone have pictures of a dual exhaust on an explorer with tips coming straight out the back? I wanted to go with this set up but id like to see it first and I don't know if it is possible to route it with the spare up underneath. Let me know and please post some pics.

The gas tank is also another obstacle.

 

[Rustang©]

From experience, it is very difficult to comfortably fit two mufflers and cats under the first gens. I tired and couldn't do it without removing my spare tire, thats the only area where you'd have enough space, even there it would be tight, especially for off roading. Not to mention having two mufflers right next to the gas tank, isn't a great idea.

If i were you i would either go one large pipe, 2.5 is plenty for a 4.0, or do one in and two out, that you could do.


I have a single with a super 40, pics and vids are in my sig, if you want to get and idea of what a single 2.5 looks and sounds like. Keep in mind i don't have cats.

Other people may have been able to fit 2 under a first gen with some creativity, so im curious to see what people have to say:

-Dan

 

[pope_face]

As with most cases, anything is possible with enough money. The question is, is it worth it? I was considering going the same route and just cramming two pipes right next to each other, following the stock path and just splitting the pipe from the driver's side header off to the driver's side after the spare... or just running them straight out back, side to side. Where it starts to get tricky is the actual physics of it... now, I'm just going to pull some numbers out of my ass, but assuming you were putting in two 2.5" pipes, that's roughly a 5" cross section per pipe, times two... so you're getting about a 10" cross section... put in one single 3" pipe, and you've got roughly a 7" cross section... now, I know that's a lot less, but you need a minimum of a 3" by 3" space to fit a single pipe in, whereas you'd need a minimum 5" by 2.5" space to fit dual pipes... the extra two inches could make a difference.

Also... you'd be able to flow more volume with dual pipes, but would you really need the extra flow? I'm not sure how many people put 3" exhaust piping on a 4.0, and the extra 3" cross section you'd get from a dual exhaust kind of seems like overkill, not to mention the difficulty in running dual pipes to the rear of the car. Any potential gains could be lost through all the bends in the pipes.

Then again, I'm no physics major, and I've only completed high school physics, so perhaps someone else has the knowledge to back me up or prove me wrong... personally I think that the cost (of parts and labour) outweighs any potential gains... you could probably get a better improvement with some other mods.

HTH,

Fil

 

[Rustang©]

I also am not a physic;s major, but i do know a little bit about exhaust technology, and pope_face you have the right idea. The largest pipe needed on a 4.0 with two cats is 2.5 inch.. Any larger is just wasted money and material.

When you use a larger pipe you reduce pressure(duh), but when you reduce pressure to a point where back pressure is non-existent, so is your torque, trust me, i lost torque, when i but on my single 2.5 with no cats.

To compensate i had to install at 2.5" --> 2" adapter at the end of the pipe, after the muffler, to create some back pressure again.

Also, the sound of your truck will be largely effected by the size of the tube, i have heard many people's exhaust on this site, and from hat i've seen, mine is one of the most closely resembling that of a V-8. It actually sounds better with the 2.5" --> 2" tip. It seems that with a flowmaster muffler, the more pressure(to a degree) the better and deeper the sounds..


Moral of the story: on a low power 4.0 explorer V-6, it is pointless to install true-dual exhaust, you will loose toque and you may not achieve the exhaust note you wanted.


-Dan

 

[ExporeRanger]

how about a 2.25 system with dual tips 2.5in each..how would backpressur and sound be outta that?

 

[Rustang©]

as long as you have a single muffler, you should be fine. Dual tips is something I wish to try, just haven't had the time to do it. If you do a smaller pre-muffler tubing, like 2.25, you should have no problem with back pressure.

Back pressure also varies greatly on the kind of muffler you buy, I have a single chamber race muffler(bad decision), you may want to buy a 2 or 3 chamber muffler, but thats your call. A sound byte of mine is in my sig and I have a super 40.

Good Luck!, and let me know how it sounds and what muffler your using.

 

[92fordxman]

yup,i had duals on my ex and they sounded good but lost power, it needed the back pressure, i love the sound of it now, 40 series, single. love the power with the costom intake.