2.5” Exhaust Clearance

[XCRN]

Will I have interference issues between exhaust and rear trackbar with a 2.5in exhaust pipe, such as the one from Banks? This will be going on a LJ with a short arm suspension and Genright Safari fuel tank if these matters. This is not going in a stock application, and I will probably have the ability to shift the position of the tailpipe slightly, I just cannot make notches in the pipe to restrict the flow further since 2.5in will already be undersized compared to the donor vehicle the engine (GM LV1) is coming from. I just had lots of issues with my LS TJ and using 3in tailpipe around the trackbar area and had to make quite a few clearance notches, but I am hoping 2.5in exhaust will be good enough for the smaller engine.

https://bankspower.com/products/exh...006-jeep-wrangler-4-0l?variant=43028889862341

 

[macleanflood]

I really had to work my 2.5" setup on my TJ. Hooker cat back, banks headers and my own 2.5" down pipe to a v-band in front of a Magnaflow 2.5 stainless cat, then slip clamp into the cat back on my 97.

Getting everything stuffed up for a tummy tuck and clearing the exhaust on full passenger stuff is challenging. I've still got work to do...but I'm on the hunt for a 2003-2006 skid (I chopped mine) so I can cut and raise the rear frame and bring the bumper and rear exhaust hanger up an inch.

-Mac

 

[DirtDawg]

My thinking combo is clearance between Genright tank, track bar and passenger side shock might need a custom tailpipe vs one like the Banks shown. Coincidentally, I have an 8am appt today 50 miles away with a 4x4 shop claiming to have expertise in custom exhaust systems. I have a new Magnaflow 2.5" OD 5"x14" round muffler with turndown tip on now which is too loud and drones. A wider can as shown would encroach on the passenger side Rubicon Express lower control arm (L-A kit). I bought a Walker-Dynomax aluminized steel tailpipe with mandrel bends designed to mate with their own muffler having offset outlet which doesn't meet with the Magnaflow muffler. I'm taking that with me with hopes it can be modified with a welded-on dogleg extension. If not, I'm open to their suggestions - so long as sufficient clearance during articulation to avoid contact rattles (or worse). As always, "no free lunch" with such modifications...

 

[XCRN]

I really had to work my 2.5" setup on my TJ. Hooker cat back, banks headers and my own 2.5" down pipe to a v-band in front of a Magnaflow 2.5 stainless cat, then slip clamp into the cat back on my 97.

Getting everything stuffed up for a tummy tuck and clearing the exhaust on full passenger stuff is challenging. I've still got work to do...but I'm on the hunt for a 2003-2006 skid (I chopped mine) so I can cut and raise the rear frame and bring the bumper and rear exhaust hanger up an inch.

-Mac

This is where I am hoping I can get a little more freedom to move the tail pipe around since I will be making a custom header back setup for a V configuration engine already.

My thinking combo is clearance between Genright tank, track bar and passenger side shock might need a custom tailpipe vs one like the Banks shown. Coincidentally, I have an 8am appt today 50 miles away with a 4x4 shop claiming to have expertise in custom exhaust systems. I have a new Magnaflow 2.5" OD 5"x14" round muffler with turndown tip on now which is too loud and drones. A wider can as shown would encroach on the passenger side Rubicon Express lower control arm (L-A kit). I bought a Walker-Dynomax aluminized steel tailpipe with mandrel bends designed to mate with their own muffler having offset outlet which doesn't meet with the Magnaflow muffler. I'm taking that with me with hopes it can be modified with a welded-on dogleg extension. If not, I'm open to their suggestions - so long as sufficient clearance during articulation to avoid contact rattles (or worse). As always, "no free lunch" with such modifications...

On my LS TJ that is an identical setup with a GR tank but 3in exhaust pipe. I had to take a fairly deep notch out of the downturn of the tail pipe to get any kind of decent down travel on the driver rear side. I plan to outboard the LJ so hopefully that might help add some routes and I really need to get the TJ done too! I was hoping to use a banks tailpipe to save some time since there really is not any exhaust shop around me that I trust to do a decent job with a stainless exhaust. If I can tack the parts together myself, I can take to many places that can do a great job welding, I just need to figure out routing my self and I am mediocre at that at best.

 

[macleanflood]

Outboard those shocks and get some room.

-Mac

 

[XCRN]

Outboard those shocks and get some room.

View attachment 647695

-Mac

Hopefully soon! I only have 1 more trip planned for the LJ this year, then all sorts of work will be happening. Tub off, frame sandblasting, powertrain swap, Rubicon D44s front and rear, proper suspension, all the good stuff that I have collected over the last 2 years.

 

[BC Moto]

I'm on the hunt for a 2003-2006 skid (I chopped mine) so I can cut and raise the rear frame and bring the bumper and rear exhaust hanger up an inch.

-Mac

Stock belly skid? If so mine is sitting next to the dumpster

 

[macleanflood]

Stock belly skid? If so mine is sitting next to the dumpster

Fuel tank skid.

I think I have at least 2-3 stock belly skids...even after selling a few.

-Mac

 

[Rickyd]

This is where I am hoping I can get a little more freedom to move the tail pipe around since I will be making a custom header back setup for a V configuration engine already.


On my LS TJ that is an identical setup with a GR tank but 3in exhaust pipe. I had to take a fairly deep notch out of the downturn of the tail pipe to get any kind of decent down travel on the driver rear side. I plan to outboard the LJ so hopefully that might help add some routes and I really need to get the TJ done too! I was hoping to use a banks tailpipe to save some time since there really is not any exhaust shop around me that I trust to do a decent job with a stainless exhaust. If I can tack the parts together myself, I can take to many places that can do a great job welding, I just need to figure out routing my self and I am mediocre at that at best.

View attachment 647692

View attachment 647693

View attachment 647694

No offense meant but i think your track bar is installed backwards.the bent section of the track bar is supposed to be over the exhaust right? Currie bars have the best clearance

 

[XCRN]

No offense meant but i think your track bar is installed backwards.the bent section of the track bar is supposed to be over the exhaust right? Currie bars have the best clearance

I THINK mine might be on the correct way, I vaguely remember if flipped it around where threaded JJ end was on frame and solid end was at axle (opposite as seen in my picture) the bar would hit the tub when not even near full compression and was difficult to install. But you do bring up a good point, why is mine this way and other bars seem to have the bend closer. Is mine actually installed wrong and I misremembered the interference? I always questioned why the adjustable end was at the axle, the most inconvenient end it seems.

 

[GoldenGorilla]

I know the LJ seems to be a bit more problematic with the exhaust routing, which I find weird considering the extra 18" of space to work in.

In my TJ,Rubicon there were no issues with a Flowmaster 2.5" catback, using a JKS adjustable rear trackbar with a 2.5" lift. It's not exactly spacious back there, but it all fit without issue. I didn't like the amount of noise the Flowmaster Delta 60 muffler introduced under the passenger seat and decided to go with a Walker QuietFlow SS muffler 2.25" stock replacement for the factory spec muffler in my 04 and I kept the 2.5" mandrel SS pipe from the Flowmaster kit. I had a good local muffler shop put it together. I would expect Banks is equally well designed to run the gauntlet over the axle, under the trackbar and aside the fuel tank.

 

[DirtDawg]

Home now from the 8am appt mentioned in post #3 and I claim success! Pics and product links used available to post upon request by the OP but in summary, the newly installed tailpipe significantly reduced dBA (droning) heard inside the cab by eliminating the turndown tip under the tub forward of the axle. With such a small muffler, it's not stealthy but most of the noise now exits where I was rather than where I am (if you get my drift)...

 

[Rickyd]

I THINK mine might be on the correct way, I vaguely remember if flipped it around where threaded JJ end was on frame and solid end was at axle (opposite as seen in my picture) the bar would hit the tub when not even near full compression and was difficult to install. But you do bring up a good point, why is mine this way and other bars seem to have the bend closer. Is mine actually installed wrong and I misremembered the interference? I always questioned why the adjustable end was at the axle, the most inconvenient end it seems.

Its hard to know with the various manufacturers. Food for thought though.

 

[BC Moto]

For clearance issues why not just a turn down after the muffler instead of going over the axle.

 

[XCRN]

For clearance issues why not just a turn down after the muffler instead of going over the axle.

I am confused, like run it under the axle out the back or dump before the axle under the tub?

 

[macleanflood]

From my perspective I often drive my 97 TJ for many hours...so anything I can do to reduce noise and fatigue for hours of freeway driving... Oregon to Moab and the Rubicon Trail for example...are key.

Yes I could see a turn down after the muffler increasing clearance at the expense of noise and fumes...and for a trail only rig probably acceptable.

I bought a TJ because I can drive it to trails and not trailer it. So my exhaust goes out the back tucked up beside the fuel tank like stock.

-Mac

 

[GoldenGorilla]

My use case is like Mac's. Many hours of highway driving to get someplace amazing. No trailer queen.

Back when I was a 20-something kid and bought the 04 Rubi new, there was a big Rubi forum meet up in Moab. Lots of people came through Denver where I live and linked up for the final leg. There was another younger guy who had come across from TN and who had put some loud muffler on his jeep. After 20 hours or whatever to get to Denver he was fried from the droning. I ended up driving his for a few hours so he could rest and my friend who was riding along drove mine. I knew then and there that I never wanted a loud exhaust on a Jeep and I never wanted to ride in that one again.

 

[BC Moto]

I am confused, like run it under the axle out the back or dump before the axle under the tub?

On my TJ I have the exhaust turn down before the axle. I chose to do this for the clearance, this is not my daily and currently drive too and from the trails and I do it in some PRP fixed seats. The muffler is a Flow master FX muffler and to me its not bad when driving it, I still have the cats and resonator in place.

 

[DirtDawg]

^^^ If you have a sufficiently large muffler canister (I like that Brits call them "silencers"), a turn down tip under the tub might be acceptable - for some. Mine with RE long arms significantly limits the maximum possible can width on the lower passenger side, thus the 5" diameter round Magnaflow I've been using with the provided turndown tip. Other generic mufflers of similar size might have also worked but I chose that one due to the welded-on flange plate for DIY installation. Ah yes, clearance problem solved but way too loud inside and out plus drone around the 2000 rpm resonance frequency! Yesterday morning, I got that fixed with combo of a model-specific Walker Dynomax tailpipe along with custom alteration to join the tailpipe with the muffler. No more turndown and far less total dBA heard inside the cab during my 55 mile drive home. Hooray!

Also noting, this TJ is a dedicated trail rig with forest access end of pavement literally 2 miles from my home at 7.4k elev. So, no freeway driving at all and limited on 2-lane State highways, depending on off-pavement routes taken.

Magnaflow P/N 17122 "Off Road Pro" shown upon installation:

 

[XCRN]

On my TJ I have the exhaust turn down before the axle. I chose to do this for the clearance, this is not my daily and currently drive too and from the trails and I do it in some PRP fixed seats. The muffler is a Flow master FX muffler and to me its not bad when driving it, I still have the cats and resonator in place.

My LJ will see a lot of on-road miles and is also going to be my daily driver and long haul road trip vehicle. It will still see off-road often but I have to drive a few hours one-way for the good stuff. I would much prefer the exhaust going out the back for comfort reasons and to minimize fumes in the cab.