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Yes, I used the search and turned up very few for the 4th gen. And of the ones that did delete, they were looking at adding in a high flow muffler with a straight pipe. This in turn would be LOUD. Not what I'm thinking of doing.

I only want to remove the resonator and the 2 pipe turns at the rear of the van. This would reduce the flow restriction of the exhaust end.

Reading the few postings of folks that have done this and keeping the original muffler, there isn't a noise penalty.

Anyone else have a been there and done that with these 4th gen vans?

O'Reilly's has the Nickson Exhaust 2-1/4 end pipe that is the perfect 18-inches long. UPC: 82852176249
Aluminized Steel for a mere $7.59. With a metal cutting disc or a hacksaw, one can do this mod using the pipe and a simple exhaust clamp. It may need a mount at the tail like the pipe does today. A simple adder too. It's only one cut. And if needed, the resonator and pipe can be fitted back on with and exhaust sleeve and the same clamp.

With the 3.8L TB mod on the 3.3L engine, this seems to be a simple compliment to help a tad for engine breathing for in and out air flow.
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Did that and a little more a year or 2 ago when the wife's van needed exhaust , so i had my exhaust put on her van !Had a custom cat back built for my T&C.

Hemi truck muffler and duel tips (from a hemi 300)
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Discussion Starter #3
Did that and a little more a year or 2 ago when the wife's van needed exhaust , so i had my exhaust put on her van !Had a custom cat back built for my T&C.

Hemi truck muffler and duel tips (from a hemi 300)
We got a RAM 2500 and I recently did the muffler with a Walker OE replacement. Didn't know one of these could fit under the van.

Is her van a stow-n-go type? That may be the difference right there. How is the sound? loud or now with a deep roar?

Nice work. Very clean welds. Good work on the 2nd cut-out for the rear bumper too.
 

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Mopar, I saw you reference this post in another thread. Did you end up doing the resonator delete? I'm one of the 3.8l TB mod fellows looking to further the breathability.
 
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Mopar, I saw you reference this post in another thread. Did you end up doing the resonator delete? I'm one of the 3.8l TB mod fellows looking to further the breathability.
I've been side lined with a health issue preventing any vehicle work like this. The best I could do was to add the heated seat covers to the front 2 seats.

My list is growing on work to be done on the van.

Others have done this already. The 18-inch exhaust pipes are easy to find at auto parts stores. Just verify the corrosion protection on these.

ALSO, save the resonator and where you had made the one cut. This way, should you ever need to go back, a simple exhaust coupler would work nicely.
 

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Just like the intake, the exhaust system was tuned by a team of NVH Engineers to eliminate harsh tones.
There is roughly zero horsepower to be gained by modifying the exhaust or intake systems on these vans as well. All the performance potential, like on most vehicles, lies in the cylinder head and camshaft design. You dont think Chrysler spent a few extra dollars per van to put bends into the exhaust and a resonator if they thought it would achieve nothing, or if it would lower performance, do you?
 

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Edy, the swap wouldn't be done in the interest of psychoacoustic optimization. From what I understand the engineers focused on designing reliable engine and transmission coupled with intake and exhaust systems calibrated to provide a smooth and silent ride. Any modifications to that system of parts is assumed to lesser the standards set by those engineers.

At least for me, it's an opportunity to learn more about working on various parts of a vehicle through first hand experimentation. And if cutting out several feet of bent pipes and restrictive resonators eases backpressure in the manifold and I gain .05 mpg at the cost of a little rear-end noise, then that's nice too.

The final step is post back results and instructions so that other users can learn something from the experiment. In my mind it is better to encourage creativity and experimentation as means to further understanding for owners and to open doors to additional experimentation - rather than quash ideas by insisting on their futility before being tested.
 

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Back pressure is a myth, the exhaust gas is at several thousand PSI when it exits the exhaust valve. The gains that can be made with exhaust are exactly the same as with the intake, by tuning the runners to the port. A properly tuned header will allow pulses of exhaust to flow through the runners at a specific velocity and pressure, such that there is a low pressure zone behind the pulse that "scavenges" exhaust out of the cylinder when the valve opens.
Too large of an exhaust pipe, and the air doesn't have sufficient momentum to scavenge. Too small of a pipe, and the velocity is so high that the pressure becomes low due to Bernoulli's Principle. Length and diameter are tuned to RPM.
We don't even have headers though, we have manifolds. 99% of the inefficiencies of your exhaust is occurring in the manifold, modifying the rest of the exhaust will just make your van louder and potentially illegal.

You'd need to find the engineering math to design a properly sized header, build said header from scratch, and mate it to the current exhaust or build a legal dual exhaust if you want to make some gains.

But, you'd be way better off bench flowing the cylinder heads or having a custom cam grind if you want performance, the intake and exhaust are very sufficient for the top end of our motors. Best horsepower per dollar would be oversized valves and camshaft.
 

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Discussion Starter #9

Just like the intake, the exhaust system was tuned by a team of NVH Engineers to eliminate harsh tones.
There is roughly zero horsepower to be gained by modifying the exhaust or intake systems on these vans as well. All the performance potential, like on most vehicles, lies in the cylinder head and camshaft design. You dont think Chrysler spent a few extra dollars per van to put bends into the exhaust and a resonator if they thought it would achieve nothing, or if it would lower performance, do you?
Not looking for a quiet ride. I'm looking to allow the flow of exhaust quicker and easy passage out of the pipe. Not looking for MORE Hp either.

This helps with engine response. This in turn helps towards MPG. Not worried if the sounds are 3 to 5 dBa louder or the tone changes. Big deal. Want the engine to breath better for the 3.3L.

Look up CFD and exhaust simulation on the web.

In CFD simulations, the more bends and walls equals more pipe turbulence and increased flow pressures. The 2 extra bends and the resonator are just that. Going straight pipe takes those out of the van's flow path. I've done this simulation a few times in ANSYS CFX software, HP 8-core I7, 256Gb RAM. It's just an extruded 3D CAD solid of 2.5-in diameter. Simple to solve in under 3mins. If I had the stainless alloy properties, I can also add in the modal analysis to see if the dBa would be affected too. Ideally, anything under 20Hz and over 70Hz is acceptable. The range between for expanding gases in a pipe gets annoying otherwise.

If folks are concerned about noise (NVH) issues, here is a general read about it.
http://ijame.ump.edu.my/images/Volume_7/6_ Jha and Sharma.pdf

I would highly doubt the NVH would change radically removing the resonator. In fact, this isn't the only thread on site here with folks not noticing any real change in noise. I've looked into a few YT vids as well.
 

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yzbw0kq1zp021.jpg

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Formula one seems to not care about bends, and they're the guys that would spend millions of dollars on something that could make a few more horsepower.
Notice they all have headers instead of an exhaust manifold too.
 

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Discussion Starter #11
View attachment 56836
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Formula one seems to not care about bends, and they're the guys that would spend millions of dollars on something that could make a few more horsepower.
Notice they all have headers instead of an exhaust manifold too.
I'm not driving a F1. Totally different application. And those bends are soooo super generous vs. the tail end bends on the minivan over the axle and then around the resonator.

Cool pix though. I've seen this plenty of times on the job during testing. Not F1 nor performance racing, just the average OE vehicle launches. The pipes have to be calculated for the hydraulic diameter and hot gas delta-T from the manifolds on back.
 

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I'm not driving a F1. Totally different application. And those bends are soooo super generous vs. the tail end bends on the minivan over the axle and then around the resonator.

Cool pix though. I've seen this plenty of times on the job during testing. Not F1 nor performance racing, just the average OE vehicle launches. The pipes have to be calculated for the hydraulic diameter and hot gas delta-T from the manifolds on back.
Formula one seems to not care about bends, and they're the guys that would spend millions of dollars on something that could make a few more horsepower.
Notice they all have headers instead of an exhaust manifold too.
Sorry I've not been around much in the past 2 weeks. Medical issues put me on the sidelines. Just getting thru the start of PT now. If the weather agrees by Thanksgiving, I may get the resonator deleted. It will take longer to jack up the van than to delete the resonator. ?

I'm trying to snag a set of those Dayton Parts Add-a-leaf under kit. I've seen these on 2 vans already. 1 really recent as a medical people transport to the clinic. It had the wheelchair access on the slider door side to the curb and the other slider door was normal. It also had a really nice high-top.
 
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