V8 Pass Side Exhaust Under the Drive Shaft?

[ThisGuyUKnow]

Dropped the Cj off at the custom exhaust shop today. I don't know a whole lot about exhausts but I know that I absolutely have to have a cross over for a Y pipe so I can get good 02 readings for my Fuel Injection.

It looks tight under the pass side and the guy said he doesnt see any way he can go over the top of the drive shaft and axle even if he brings the tube in front of the oil pan. Do I take his word on this? The engine appears to be in the correct postion for a v8, obviously the 360 isnt a stock engine but the AMC 304 was and they are dimensionally the same on the exterior. So I can't figure out why there isnt enough clearence between the axle and the engine to go around the front of the pan.

If I let him go under the shaft I am worried that the drive shaft will impact it. I'd think that the drive shaft would move up more than it would move down while flexing but I am not too sure on this. I wont be rock crawling so the clearence issue of going under the shaft wouldnt be an issue. Has anyone ever routed the exhaust that way?

 

[gert]

last I remember, the passenger tube goes across between the oil pan and front of tranny and then runs out the back on the drivers side(single exhaust) my v8 dual exhaust does not go under or over the the drive shaft it goes beside it and beside the Transfer Case what if he goes around the back of the Transfer Case to tie it in? see pic of one one jeep http://www.delawareja.com/gallery2/...j7-exhaust-options-sidepipes-too-loud-596873/
http://www.jeepsunlimited.com/forum...dealt-with-V8-exhaust-heat-and-your-fuel-line

 

[ThisGuyUKnow]

The first link did not work. Behind the TC would be an Idea except it looks like you wouldnt be able to fit a cat and a muffler. i guess you could put two cats on it but I think that would be problematic with the o2 sensor being after the cat.

 

[thistle3585]

Mine is as Gert described, but I cut mine just aft of the Transfer Case and put a 90 degree elbow pointing it down because I got tired of the exhaust being pulled in from the rear.

 

[Hedgehog]

DON"T allow him to run the exhaust pipe under the driveshaft. Bad move, you are just asking to crush it on something. Cross over tubes generally go as Gert wrote. Between the back of the oil pan and the front of the Transmission . I've got headers and duel exhausts with cats and mufflers running inside the frame which creates additional space issues, but it can most certainly be done.

 

[Purple77CJ7]

I agree with the others with crossover running in front of tranny. I run dual cats and mufflers and have my o2 sensor on the passenger side bank only and it runs fine. Running Howell throttle body set up.

 

[ThisGuyUKnow]

I agree with the others with crossover running in front of tranny. I run dual cats and mufflers and have my o2 sensor on the passenger side bank only and it runs fine. Running Howell throttle body set up.

I'm leaning towards duals all the way through. with the o2 on one side.

I don't know if that would be a waste though because I want it quiet. Did anyone with dual exhaust to an h it x pipe? Ben doing some light research and it seems those are good to add vs a true dual for performance.

another option I am weighing is bringing the y behind the tc like in the link gert provided . I would think with that set up I would still need two cats due to Limited space after the y. the o2 would still be on one collector in this method.

with either of these methods I may be able to go with the hedman headers that came with my jeep. I took them out because of how far back they came, they were not conducive for a y pipe near the engine.

any suggestions onwhat size pipe to use? those with dual pipes where in the rear are you bringing out the tailpipes. Don't want to bring them out under the tires but don't want exhaust getting sucked into the cab either.

 

[Purple77CJ7]

With dual exhaust it is going to be a very tight fit, I don't think you will have room for an H or Y pipe, then you will be back to routing around the driveshaft. My tips come out behind the rear tires in between the frame and the springs. They originally dumped under the Jeep ( from the previous owner) and you get a lot of fumes inside the Jeep. I had mine installed by a muffler shop, they made everything fit nicely. They used some small cats and I had them install Magnaflow mufflers, and 2.5" pipe. I like a nice mellow rumble. You can install quieter mufflers.
You can just see the right tip sticking out behind the tire.

 

[gert]

I have true duals on mine, very quiet. I told muffler shop to do 2.5 all the way back and 45 it out at the corners and I dont want to hear it, it is a tight fit but was great I have to do some "adjusting" since I have rotated the Transfer Case up. if you still want a cross over do it after the T case. If you are looking for the extra horse power then put the Hedmans back in. You might look at the collector flanges and head flanges to see if you think they will leak before you put them back on though

 

[ThisGuyUKnow]

I have true duals on mine, very quiet. I told muffler shop to do 2.5 all the way back and 45 it out at the corners and I dont want to hear it, it is a tight fit but was great I have to do some "adjusting" since I have rotated the Transfer Case up. if you still want a cross over do it after the T case. If you are looking for the extra horse power then put the Hedmans back in. You might look at the collector flanges and head flanges to see if you think they will leak before you put them back on though

is that the spacer you said you made for your NV3550 to clear your throw out i see in that picture? Do you have pics of that finished spacer? Can you make another?

BTW I talked to the shop. They put the hedmans back on and are running the passenger side manifold over the tc to a y just after the Crossmember. He said there was plenty of room to do that currently and even if I lift it later on the tc is either going to stay in the same place or come down if I lift it later. Since the y is so far back, going to install the o2 sensor in the driver side collecter and ad another bung to the pass side so I can swap it out or get diagnostics for future tuning.

 

[gert]

is that the spacer you said you made for your NV3550 to clear your throw out i see in that picture? Do you have pics of that finished spacer? Can you make another?

BTW I talked to the shop. They put the hedmans back on and are running the passenger side manifold over the tc to a y just after the Crossmember. He said there was plenty of room to do that currently and even if I lift it later on the tc is either going to stay in the same place or come down if I lift it later. Since the y is so far back, going to install the o2 sensor in the driver side collecter and ad another bung to the pass side so I can swap it out or get diagnostics for future tuning.

yes that is the spacer at the back of the block, I used the old tranny/engine shield as a pattern. I am currently unable to produce another one because I am not home. Its pretty easy though if you can get a hold of some .25 aluminum and drill it to match I had to cut it like a ring because the flywheel weight was rubbing on it

 

[johnbilt]

I have duals out the back on my 360. 2.5" all the way. I am changing the rear part to make a turnout behind the rear tire. Tends to suck exhaust in the cab if I open the rear window in the summer.

Not much room for a crossover, but may make the whole rig quieter.

The O2 sensor needs to be as close to the cylinder head as possible. I have mine mounted right at the output of the manifold. One side works fine. I don't have fuel injection, but I have a monitor for Air/Fuel ratio so I know what my carb is doing.