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PERFORMANCE EXHAUST

jeeper50

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Speaking as a diesel truck owner a larger and straight thru muffler does help move more air thru your engine.
 

adam8504

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I totally agree most of the kits are sold out though. I can get the magnaflow for around $100 and have a really good exhaust shop near me. I dont want to pay a ton of money for a bolt on kit if I can get the same results with this muffler and my guy welding it in
 

BoxofRox

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You'll have some gains I'm sure, Dyno testing has proven that the factory muffler is restrictive. At the 200+ horse level, the stock cat was worth only a horsepower or so to remove, it flows very well. The stock exhaust from there back gained around 10 horse going to a straight through muffler with 2.25" pipe
 

BoxofRox

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I've used the Magnaflow you linked in your post on some vehicles, never a diesel though. It doesn't do too much to attenuate sound in my experience. Also, the cat does a lot to kill the diesel smell and some noise. I'm in no way a "green weenie" or a tree hugger, but in the case of a Roxor the benefits of the cat outweigh the single downfall, which is after some time it may begin to clog.

A full 2.5 inch system will be loud, but how loud is too much is a matter of individual preference. My cat back 2.25" system has a flow through muffler and it's perfect for me, great sound without being too loud. Under load in some situations it barks pretty good, wouldn't want it much louder. And one other thing, you'll really like side exit better than rear. Rear exit will swirl the fumes right back up to the passenger area and you'll eat fumes while driving. Side exit avoids 90% of that issue and VERY rarely you'll catch a whiff of exhaust
 

Roxasuras

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I've used the Magnaflow you linked in your post on some vehicles, never a diesel though. It doesn't do too much to attenuate sound in my experience. Also, the cat does a lot to kill the diesel smell and some noise. I'm in no way a "green weenie" or a tree hugger, but in the case of a Roxor the benefits of the cat outweigh the single downfall, which is after some time it may begin to clog.

A full 2.5 inch system will be loud, but how loud is too much is a matter of individual preference. My cat back 2.25" system has a flow through muffler and it's perfect for me, great sound without being too loud. Under load in some situations it barks pretty good, wouldn't want it much louder. And one other thing, you'll really like side exit better than rear. Rear exit will swirl the fumes right back up to the passenger area and you'll eat fumes while driving. Side exit avoids 90% of that issue and VERY rarely you'll catch a whiff of exhaust
I didnt realize that about the exhaust location, but now I remember my father telling me that about a spoiler looking device he had on a 1983 Cherokee we had (wish we still had it) :)
 

Colderweather86

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Speaking as a diesel truck owner a larger and straight thru muffler does help move more air thru your engine.
Being 62HP stock, and that little bitty turbo, there will be nothing to gain with a straight through exhaust except more sound. The muffler is non restrictive already.
 

adam8504

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Im also doing stage 2 tune from diesel freak and their intake connection and egr delete so should I leave the exhaust stock or would it be beneficial to have at that point
 

Colderweather86

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Im also doing stage 2 tune from diesel freak and their intake connection and egr delete so should I leave the exhaust stock or would it be beneficial to have at that point
I have all of that, plus the RX41 with the stock exhaust. I haven't noticed any exhaust leaks from pressure, and there is no evidence from anyone that the stock exhaust is restrictive with double the power.
 

BoxofRox

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Other than dyno numbers from Calibrated Power.


Yes, they're making big power but regardless of that, more flow from a better performing exhaust is good at any HP level
 

Colderweather86

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They also have a CP3 pump, which takes the engine way beyond what a tune can get you.
 

BoxofRox

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Agreed, and it's also very expensive.

However when you add a boost valve in your wastegate line, or a bigger turbo (very nice, by the way! (y)) you are increasing the airflow through the engine because increased boost pressure is more compressed air flowing through. The tiny 2" factory piping designed for low boost and especially the factory muffler are restricting your added air on it's way out. The muffler is a spark arrestor, check out how those are made inside, restriction city! :oops:
 

Colderweather86

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I'm sure with the Stage 2 and the RX41 there is a restriction that could eat up a few HP's, but most people are never going to be using all that power for extended time to see a change in performance. Those 1-2 HP to keep my tires spinning when I'm about to get stuck.
 

adam8504

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Well I think I'll go cat back with a staight through magnaflow ill post a clip of the sound when I get it all done
 

Paulson

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The 2 1\2 is a little loud for me. I think a lot of that was the cat. Biggest thing for me on the 2 1\2 was it moved the down pipe inside of the frame rail I play hard with mine. And had a few good dents and scales on my cat
 
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