Hey guys,

Quick question i plan on running a true dual setup for my 98 cherokee. I have already installed pacesetter 3/3 long tube headers. My current setup is 3/3 manifold into collector to single.. the o2 is mounted in same location as stock.. Now i plan on eliminating the y collector and running 2 single pipes, 1 on driver side and 1 on passenger side... to solve the scavenging i plan to install an h-pipe..

Now my real problem and the reason for this thread is the o2 sensor location. My vehicle only has 2 sensors upstream and down stream. I know the purpose of the sensors (upstream for air/fuel) (downstream deference in air/fuel. Basically to make sure there's a cat there)...

My question is where can i place the o2 sensor?? i know it would be best to have the sensor read all 6 cylinders but it would no longer be considered a true dual.. or can i place the sensor on one pipe near to the manifold to gauge the air/fuel/temp. The second would be placed in the middle of the h pipe since there wont be to much air or fuel in that pipe its just the for scavenging...

The second option would be to install and x pipe and place the upstream in the middle of the crossover. But it would have to be done close to the manifold for heating purposes. and the x wouldnt be so large very small design just to have the o2..

I prefer the h pipe vs x pipe for sound purposes but need and expert opinion on 02 location whether it HAS to read all cylinders or if it can only be 3 cylinders and not cause any timing and firing problems...

Any and all info will be taking kindly and put into consideration. Thank you for the help.. this is the only thing keeping my Jeep parked..

 

an inline 6 cant have true dual exhaust

 

i miss read how you were going to do it

 

Moved to Tech...

 

No real majic to a O2 sensor, it's a thermocouple. As it is heated two dis-similar metals create a small voltage (mv.). The sensor does not monitor any one cylinder, it's just measuring the temperature of the exhaust stream. Upstream/downstream on one pipe will suffice.

 

ok thank you... will the tempature vary from 3 cyl to 6cyl?

 

ok thank you... will the tempature vary from 3 cyl to 6cyl? or should i get the same voltage?

 

How are you goin to run true dual? The only way I know how to do it would to run a y pipe after the cat and the rest of the way to the back

 

I've been contemplating this as I have an extra uncracked exhaust manifold from the jy for someone and they never got it from me. We have a welding shop where I work and I can get any sort or exhaust tubing of various angles as well at work. I also wondered about the O2 sensor and also about where to run it. BUT before I waste anymore time even considering it. What would be the advantage of having dual exhaust? Other than just having it to be cool of course.

 

Pacesetter headers.. are two 3-1 pipes giving me 2 outlets..
Run two seperate 2 1/4 pipes down each side of vehicle, install cat conv and muffler in stock location/ passenger side, and same on drivers side.. for right now i will have a turn down tip cuz i have to do suspension work before i run back. The H-pipe will be after the trans mount bracket and underneath the trans tail/driveshaft.

o2 sensor(s) will be placed on each bank 1,2.. and will be monitored by a/f gauges. only one sensor will conncted to factory harness which will determine a/f ratio. <(placed on bank 1). the second is connected like factory but will not send signal to ecu.. only to a/f gauge.

Judging by the gauges i will be able to dtermine if each bank is is monitoring the same a/f. at any time i can swap sensors and see if there is any difference in overall engine performance and a/f differences..

so thats it in a nut shell.. should work but need to get it done and see.. In theory im good, but this is a test/modification. Ill post some picks and video of the work done and finish product. should be interesting how it turns out..

 

yea i just wanna try and be cool and do something different.. but later on in this project/ soon to be DD, i would like to find a way to modify our beloved bulletproof engines for more hp and torque.. I dont want to tell my secret and it has been done before for other reasons. im building a well rounded street/ drag xj. I love this car and have seen the potential they have in any form of driving. Not to many people attempt it with this vehicle, and since i never had a chance with 93 sport i always wanted to buy another i finish what i started...

After the exhaust is done next step will be suspension, i want to lower its center of gravity. we know these things handle pretty damn well so im attempting to make it handle better.. im different and this will fit in perfectly with my personality.

hope you guys like the idea, ive been keepin it secret a for a lil time.. but im starting to come around and seeing progress..

Edit: You asked about advantages, well not sure if there are any at this point, for now its sound and flow..

 

haha your going to have aero issues which of course you know. They make those blacked out headlight covers that cover your front turn signal and head lamps that i would suggest getting just to eliminate those two air pockets and then completely remove the roofrack. Also some plexy glass or w/e to eliminate the air pocket in the rear bumper. I have seen stuff like this come up in some eco forums while playing around on google to get better gas mileage but same theroy. Good luck

 

Lol yeah i read about those theories to but its still a box.. nothing much we can do about that but making additions will actually help.. Underbody areo plates that direct the air and create down force.. center skid plate as well to keep flow moving and full skid plate that difuses the air and helps with that back swirl we get.. also a small speedstur wing on the hatch might look ok, but idk yet.. The rack is removable so no need to take it completely off..

 

right. lol good luck finding skid plates that are only say 1/8th in if you do decide to got that route. I have seen a white xj that was really fast on youtube but i have not idea about it or what it even ran lol.

 

yup i know about him, worlds fastest jeep, i too would like to make it there but this is street/ and occasional drag. until engine goes in. but i will just make my own i know a few metal shops that will shape it for me, if any reinforcment is needed it will be added, while trying to keep it light.