Is there a quiet yet efficient exhaust? - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep Wrangler Forums > TJ Wrangler Technical Forum > Is there a quiet yet efficient exhaust?

Introducing MONSTALINER™ UV Permanent DIY Roll On Bed LineRough Country Jeep Suspension Deals at Rockridge 4WD!Engo winches available at www.rockridge4wd.com! Free shipp

Reply
Unread 12-03-2009, 10:53 AM   #1
roadbosstx
Registered User
2003 TJ Wrangler 
 
Join Date: Dec 2007
Location: Texas Panhandle
Posts: 92
Is there a quiet yet efficient exhaust?

I am wanting a new cat back system for my 4.0 and like a relatively quiet exhaust on my Jeep. Never have enjoyed a loud 6 banger, love V-8 muscle though. Who makes a good quiet yet efficient system? And how can you tell if your cat is plugged, without tearing it apart?
Thanks!

roadbosstx is offline   Reply With Quote
Unread 12-03-2009, 12:33 PM   #2
LandoCommando
Registered User
1997 TJ Wrangler 
 
Join Date: Oct 2007
Location: NY - upstate/central
Posts: 1,055
I think the stock muffler may be your best bet. Optimized specifically for the engine and the keeps the decibels in line.
__________________
Signatures are for attention whores.


Oh the irony.
LandoCommando is offline   Reply With Quote
Unread 12-03-2009, 01:48 PM   #3
BlueFlame
Registered User
2003 TJ Wrangler 
 
Join Date: Mar 2006
Location: Oregon USA
Posts: 8,398
I love the Dynomax cat back system I have. Only a touch louder than stock, but sounds better. Hardly hear it inside, and not at all at highway speeds. Plus it wasn't very expensive.


If anyone needs one, I still have the stock system (from the flange back) in perfect condition.
BlueFlame is offline   Reply With Quote
Unread 12-03-2009, 04:34 PM   #4
roadbosstx
Registered User
2003 TJ Wrangler 
 
Join Date: Dec 2007
Location: Texas Panhandle
Posts: 92
Thanks. Sounds like the Dynomax cat back is what I want. Don't mind a little extra sound.
So, does anyone know how to tell it the cat is plugged, short of replacing? I have 97K miles, if that makes any difference.
roadbosstx is offline   Reply With Quote
Unread 12-03-2009, 05:48 PM   #5
tlendt
Registered User
2004 TJ Wrangler 
 
Join Date: Mar 2008
Posts: 141
Couple different ways of looking for a plugged cat. The easiest, though least conclusive is the vaccuum guage. Find a good manifold vac port, hook it up and start the engine. Slowly raise engine speed and watch the vac. If it starts to drop drastically at higher speed its a candidate. Another option if your hardware isn't solid rust is to pull the cat and look into it with a bright light on the other end. Today's cats are "monolithic" meaning one piece. Its like a brick with hundreds of holes straight through it, and you should see light through the holes.
tlendt is offline   Reply With Quote
Unread 12-04-2009, 07:09 AM   #6
roadbosstx
Registered User
2003 TJ Wrangler 
 
Join Date: Dec 2007
Location: Texas Panhandle
Posts: 92
Thank you tlendt! Those are the best two ideas I have heard yet. I will try the vacuum test. Probably won't do the light test through the cat until I at least have a new cat back system.
roadbosstx is offline   Reply With Quote
Unread 12-04-2009, 07:35 AM   #7
YakYak
Registered User
 
Join Date: Sep 2009
Location: VA
Posts: 12
I have used Dynomax products and would recommend them. A little more exhaust note, but not obnoxious at all.
YakYak is offline   Reply With Quote
Unread 12-04-2009, 07:58 AM   #8
Panhead
Registered User
1994 ZJ 
 
Join Date: Nov 2009
Location: NorthWest
Posts: 84
What about Magnaflow? Would you put this in the same class as the Dynamax? As opposed to the Flowmaster. I'm in a similar situation.

I went to a muff shop and the guy had a CJ with a 4.0 and a flowmaster on it. He said from his experiance the Magna was too quiet for the Jeep. He said the Flow 40 was even too quiet for his liking on his Jeep. He started it up and I tended to agree, it was weak. For a 40 seires. I was interested in Magna and he showed me a Flow that didn't impress me.

The reason I was wanting to go with the Magna is the said 'growl' as opposed to roar of the Flow. Besides, I think a 6cy just doesn't work for a 'roar'.

So, back to my question. Do you think the Magnaflow is in the same class as the Dyna, as far as low growl, as opposed to loud roar...(if you could call it that on a 4 liter)?
Panhead is offline   Reply With Quote
Unread 12-04-2009, 08:44 AM   #9
1orangews6
Registered User
2001 TJ Wrangler 
 
Join Date: Jan 2008
Location: Chattanooga,TN
Posts: 155
I have had Magnaflow catbacks on every vehicle I have owned and they have always sounded great!
1orangews6 is offline   Reply With Quote
Unread 12-04-2009, 09:39 AM   #10
bige2533
Registered User
1999 TJ Wrangler 
 
Join Date: Jan 2004
Location: Thornton, CO
Posts: 742
You want better performance but you still want the sound reduced? Next thing you'll say is that you want it for cheaper than other aftermarket exhausts cost.
__________________
Mud is good
bige2533 is offline   Reply With Quote
Unread 12-04-2009, 10:02 AM   #11
jgorm
Web Wheeler
2006 LJ Wrangler 
 
Join Date: Aug 2007
Location: San Diego
Posts: 2,355
Quote:
Originally Posted by tlendt View Post
Couple different ways of looking for a plugged cat. The easiest, though least conclusive is the vaccuum guage. Find a good manifold vac port, hook it up and start the engine. Slowly raise engine speed and watch the vac. If it starts to drop drastically at higher speed its a candidate.
That is a tricky test because vac is proportional to load. Higher rpms and no load = high vacuum. You could use a scangauge to watch the MAP. The best test would be at WOT where vacuum should be close to 0. I'm still not sure it would show if your cats were clogged. The best test would be to install a pressure gauge in the front o2 port and watch it at WOT.
jgorm is offline   Reply With Quote
Unread 12-04-2009, 10:10 AM   #12
tlendt
Registered User
2004 TJ Wrangler 
 
Join Date: Mar 2008
Posts: 141
I was working for GM in the early to mid 80's and we had many issues with the old bead type cats. The vaccuum guage is indeed an effective means of diagnosing a restricted exhaust. Have to use your brain a little to interpret the results.
tlendt is offline   Reply With Quote
Reply
Thread Tools


Suggested Threads





Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.