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"Delete Loop" pipe safe for Pentestar?

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Old Aug 10, 2014 | 07:15 AM
  #1  
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From: crystal River,florida
Default "Delete Loop" pipe safe for Pentestar?

I am ignorant to the reason for the "Loop Pipe" on the drivers side exhaust of my 2012 JK. Does anyone know the engineered reason for the loop pipe? I am one of the 2012 JK's that needed a drivers side head replacement and the extra heat creating back pressure provided by the "loop" couldn't have helped the situation in my drivers side head right?
Well here is my question and I direct it to those who either know first hand due to being an engine tech or someone who has had a engine tech explain it to them.

SHOULD I DELETE THE "LOOP PIPE" ?????
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Old Aug 10, 2014 | 07:25 AM
  #2  
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If I'm not mistaken the idea of the loop was to balance the left and right banks. Wether or not it makes a difference I'm not going to guess.
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Old Aug 10, 2014 | 07:26 AM
  #3  
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Originally Posted by spanky1989
If I'm not mistaken the idea of the loop was to balance the left and right banks. Wether or not it makes a difference I'm not going to guess.
I find it hard to believe myself that that was not an engineered solution to an imbalance as you say but am just guessing myself. Hoping someone has an anser.
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Old Aug 10, 2014 | 07:30 AM
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It is for balancing the left & right pipes. I have not heard of issues or concerns of deleting the pipe.
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Old Aug 10, 2014 | 08:13 AM
  #5  
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Originally Posted by Jeepstin12
It is for balancing the left & right pipes. I have not heard of issues or concerns of deleting the pipe.
No offense but that doesn't make sense unless "balancing" is not needed........................so an unbalanced system is as good as a balanced system............................confusing.
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Old Aug 10, 2014 | 09:43 AM
  #6  
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The reason for the loop is it makes tuned equal length exhaust from left and right bank going into the collector.

With a properly tuned exhaust system the exhaust pulse from one cylinder creates a low pressure vacuum behind it that actually helps accelerate the exhaust gas pulse of the next firing cylinder down the pipes. This increases efficiency and performance (any motorhead will tell you an engine is nothing more than an air pump). Guys building custom engines/exhausts for performance applications will spend days, if not weeks or months, designing their exhaust system to squeeze every last HP and Lb/foot out of their motor.

Is it necessary to have that exhaust loop? No. BUT Jeep spent a lot of time and money putting it in there and auto manufacturers don't waste money on pointless parts. You'll "PROBABLY" lose some power...I say probably because you may luck out and delete JUST ENOUGH exhaust tube to remain tuned (probably not, think lottery odds) or the loss of power may be so small you don't notice it. But seeing how the Pentastar engine isn't a power house to begin with how much are you willing to lose?

As for your comments about the head problems, no the exhaust loop (or deleting thereof) will not contribute to the failing heads.
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Old Aug 10, 2014 | 12:18 PM
  #7  
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I went to a muffler shop to have my y-pipe crossover moved back to make more room for the front driveshaft to droop. This shop has been in business since the 70s and is the best in my area (okay, that's my opinion). When my rig was on the lift, I pointed out the loop to the owner. He said that was the stupidest design he has ever seen. I responded that it makes the right and left bank pipes equal length to control back pressure. He laughed. He said that if one side is moving faster than the other, the faster side will "draw" the slower side to equal pressure when it passes through the y-pipe and merges. He figures they put that there to control resonance (sound).

Take out of that what you will.
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Old Aug 10, 2014 | 12:39 PM
  #8  
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Once i installed my RK long arm on my 14 i cut the loop out and had a muffler shop reroute the exhaust and i experienced 0 performance lose.
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Old Aug 10, 2014 | 01:59 PM
  #9  
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Originally Posted by Captain Obvious
The reason for the loop is it makes tuned equal length exhaust from left and right bank going into the collector. With a properly tuned exhaust system the exhaust pulse from one cylinder creates a low pressure vacuum behind it that actually helps accelerate the exhaust gas pulse of the next firing cylinder down the pipes. This increases efficiency and performance (any motorhead will tell you an engine is nothing more than an air pump). Guys building custom engines/exhausts for performance applications will spend days, if not weeks or months, designing their exhaust system to squeeze every last HP and Lb/foot out of their motor. Is it necessary to have that exhaust loop? No. BUT Jeep spent a lot of time and money putting it in there and auto manufacturers don't waste money on pointless parts. You'll "PROBABLY" lose some power...I say probably because you may luck out and delete JUST ENOUGH exhaust tube to remain tuned (probably not, think lottery odds) or the loss of power may be so small you don't notice it. But seeing how the Pentastar engine isn't a power house to begin with how much are you willing to lose? As for your comments about the head problems, no the exhaust loop (or deleting thereof) will not contribute to the failing heads.
he did much better. I simply reused another guys verbiage. This sums it up.
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Old Aug 10, 2014 | 04:16 PM
  #10  
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It is definitely there for a reason the engineers thought worthwhile.

I did get a rough country skid plate for it because it is just waiting to kiss a rock!

No way I would remove it, just get a skid plate.
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