Aftermarket Exhaust, how hard and would help any w the 4.0L SOHC?

[DenverDude2002]

Hi all,

I'm thinking about putting an aftermarket exhaust system on my Explorer (its a 2000 Sport with the SOHC V6). I don't want to go to crazy, just a cat back with a magna flow or something. I did that on my 1998 Cherokee about 5 yrs ago and it seemed to help a bit, of course it had the old school I6.

So questions are, will it help in power/mpg at all, and how hard is it on these and is it even possible to do on a sport?

Thanks

 

[Rosscup]

its very easy if you have a welder and a pipe bender hp and mpg im not sure of. good luck

 

[Nocturnall]

I some times wonder if the search button is invisible.....nope it's still there.

Search. Most every question you have to ask has most likely been covered a few times before. I have a 97 sport, I have after market flow master with it dumping right off the muffler since I don't have a welder or pipe bender. Yes it should help mpg and hp. 2.5 inch piping from the cat back is what you want to maintain back pressure.

 

[Sams01XplrSprt]

I got dual 40 series flowmasters on my 01 sport and i got the 4.0 sohc engine and big difference in sound.

 

[huntersteve61]

I won't jump on you about searching but I have found everything I needed to know already listed.

That said, yes it makes a sound difference I dont' care what people say the mpg, hp gains are marginal if not nonexcistant. It does give it a nice sound, Flowmaster 50 SUV in my opinion still keeps backpressure.

 

[aldive]

Pick the muffler of your choice and go to a local exhaust shop and have them make a custom cat back for you.

Good luck ....

 

[gijoecam]

In *some* cases, opening up the exhaust can hurt performance. The 4.0 SOHC is one of those cases... Removing the exhaust back-pressure on the SOHC generally causes a decrease in low-end torque. (Or so I've read after nearly a decade on here)

-Joe

 

[DitchWitch]

In *some* cases, opening up the exhaust can hurt performance. The 4.0 SOHC is one of those cases... Removing the exhaust back-pressure on the SOHC generally causes a decrease in low-end torque. (Or so I've read after nearly a decade on here)

-Joe

So what are you saying? Leave the stock muffler? Buy a certain type? Dont change the tubing size?

 

[gijoecam]

ALl I'm saying is what I said: It's been the experience of many members on this board that installing an aftermarket system of any sort that results in reduced back-pressure generally sacrifices low end torque. There's a thousand different ways around it... some run stock diameter tubing, some replace with like-sized parts.... ti just depends. You can install any of a million different possible combinations of headers, cats, mufflers, and pipes, and each system will have its pros and cons. There is no one right way to solve that equation.

For me, I went with the 'if it ain't broke, don't fix it' mind-set until the muffler rotted out. Then, I replaced the muffler with a Flowmaster 50 series Performance/SUV muffler and left the OEM tailpipe in place. I've been quite happy with it, but my solution doesn't work for everyone.

If you're replacing it, go wild. Do whatever you see fit. I'm not trying to sway your decision, just trying to give you some information so you can make an informed choice, that's all.

-Joe

 

[aldive]

Joe, I have not seen that with my 2 1/2" cat back,

 

[Afboy143]

2.5" piping is actually recommended for the SOHC motor. Anything more would cause reduced back pressure....

 

[gijoecam]

Joe, I have not seen that with my 2 1/2" cat back,

Correct me if I'm wrong, but isn't the factory plumbing also 2 1/2"?

I've read more than a few counts on here of guys that have run 3" thinking it would sound good and help power, only to learn they've lost the low-end grunt they used to have. Reducing the tube diameter seemed to be the general consensus that worked the best to get the low-end grunt back.

I have no personal experience either way. I've only replaced my muffler.

-Joe

 

[aldive]

The factory on the SOHC is only 2 1/4".

 

[gijoecam]

Aah, OK... Gotcha.

I forget: Did you dyno before and after the exhaust install? Just curious, that's all...

 

[aldive]

Joe, no dyno prior to the install.

 

[Afboy143]

The factory on the SOHC is only 2 1/4".

The SOHC is dual 2" pipes from the headers to the muffler, then the muffler is a single 2.25" out. Its actually recommended on our motors to have a single 2.5" pipe out of the muffler. I have 2.5" pipes from the headers back to a Y pipe that goes into a single 2.5" then to a muffler and out the rear. I noticed no loss in back pressure.

I did notice a loss of low end power when I ran a dual in/dual out 50 series muffler with dual 2.25" pipes out the rear



Just thought Id throw that out there.

 

[prayforsurf]

Im replacing my stock 2.25 pipe from the muffler back with 2.5 pipe ( i have the new muffler, and y pipe etc) just wondering if anyone knew of a few good places to pick up the pipe that goes from the muffler back, but i need 2.5 not stock 2.25 which i have on the car right now. I called midas to see if i could bring in my stock pipe to be copied on 2.5 pipe but they are very vague and the lowest they were willing to say was 50 bucks.

that just seemed a little steep for just bending up a new pipe and giving it to me...am i wrong?

ps i dont want them to do it all, i have a welder so id rather not pay them to do what i can do myself, all i need is the 2.5 pipe.

 

[Afboy143]

Im replacing my stock 2.25 pipe from the muffler back with 2.5 pipe ( i have the new muffler, and y pipe etc) just wondering if anyone knew of a few good places to pick up the pipe that goes from the muffler back, but i need 2.5 not stock 2.25 which i have on the car right now. I called midas to see if i could bring in my stock pipe to be copied on 2.5 pipe but they are very vague and the lowest they were willing to say was 50 bucks.

that just seemed a little steep for just bending up a new pipe and giving it to me...am i wrong?

ps i dont want them to do it all, i have a welder so id rather not pay them to do what i can do myself, all i need is the 2.5 pipe.

I bought some mandrel bent pipe online and got a buddy of mine to fab up a tail pipe for me. This was around 50$ so midas isnt ripping you off. I believe they press bent their pipes, not mandrel tho

 

[prayforsurf]

I bought some mandrel bent pipe online and got a buddy of mine to fab up a tail pipe for me. This was around 50$ so midas isnt ripping you off. I believe they press bent their pipes, not mandrel tho

oh cool, thanks for the info man.

 

[TheEnforcer98]

Might as well post here rather than make my own thread.

I've been looking into getting a new muffler/exhaust for some time. Just happens that my 18th b-day is coming up, so I'm gonna be getting a Flowmaster Series 40. Just out of curiosity, I took a look under my 2000 Eddie Bauer 4.0 SOHC today in the school parking lot. To my surprise, my exhaust goes like this:

Engine = 2 headers ===>-----|Muffler|---------Tailpipe

The headers already meet at a Y-pipe about 2 feet before the muffler, and enter the muffler as one. From what I've read on here, thats pretty abnormal. Anyone ever hear of this before??


Background: My uncle bought this brand new in 2000, and has babied it, and kept ALL maintenance records/purchasing info of it, and nothing says anything about the exhaust.