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DISCUSSION => General Topics => Topic started by: Tonyb on September 11, 2006, 12:10:16 AM

Title: Lost Cat (converter)
Post by: Tonyb on September 11, 2006, 12:10:16 AM

My cat came loose inside and is making a lot of noise,even at idle. I'm going to punch it out and put it back on but I was thinking about removing the resonator (Pre-muffler) at the same time from my SuperSprint cat back setup. I ran the SS before w/out cat, and noticed an HP and fuel increase, but had to put on the cat for visual inspection. If I take out the pre-muff, it will flow more, but I don't know how loud it will get! Can anyone with a muffler only setup let me know? I can handle a few more decibels but I don't want to wake up the nieghbors or sound like a Honda!:confused:

Title: Need opinions, suggestions!
Post by: Tonyb on September 12, 2006, 12:48:49 AM

I have to take my car to the shop for the above work, but I want some help regarding the decision to remove the pre-muffler along with punching out the cat???

Title: Lost Cat (converter)
Post by: MustPayDaddy on September 12, 2006, 03:14:18 AM

im running a dynomax muffler with no resonator and it sounds fine. the cops dont look twice at me.  as for the cat i say dont punch it out, either get a replacement oem or aftermarket cuz it seems youll have to go through another inspection in a year or two...

Title: Lost Cat (converter)
Post by: D. Clay on September 12, 2006, 11:24:41 AM

Magnaflow converter is $60. Weld-in.
http://www.magnaflow.com/02product/02converters.asp (http://www.magnaflow.com/02product/02converters.asp)

Title: Converter
Post by: Tonyb on September 12, 2006, 04:58:45 PM

Quote from: MustPayDaddy

im running a dynomax muffler with no resonator and it sounds fine. the cops dont look twice at me.  as for the cat i say dont punch it out, either get a replacement oem or aftermarket cuz it seems youll have to go through another inspection in a year or two...

We only have to pass a visual inspection where I live! A friend of mine works for a dealership with the sniffer test and my car passed without a cat!

Title: Lost Cat (converter)
Post by: jeingold on November 12, 2006, 12:17:32 AM

Are you using a dynomax muffler without the cats? How does it sound?

Title: Lost Cat (converter)
Post by: bmwman91 on November 12, 2006, 12:33:23 AM

Replace the cat.  It will sound really raspy without a core in there.

Don't bother cutting the resonator.  It causes NO restriction in the SuperSprint unit.  It is straight-through...just has perforated pipe with packing around it.  I dropped a stone through mine and it fell straight through.  Without the resonator it will sound bad....I chopped it off of my first car's stock exhaust and it sounded like crap.

Title: Lost Cat (converter)
Post by: StreetSpec_iS on November 12, 2006, 11:07:34 PM

mine sounded like shit, and also didnt 'feel' very healthy when i was running no cat.

Title: Lost Cat (converter)
Post by: Alpine003 on November 13, 2006, 11:45:35 AM

I hope you don't have a white car...

Also, make sure the welds for the heathshield isn't cracked. Some people think they have a bad cat when it's really just a loose heat shield.

Title: Lost Cat (converter)
Post by: rfritz on November 13, 2006, 09:46:52 PM

The can on my cat section is loose. I was thinking about removing the cat can and replacing it with a section of pipe, but I think I am going to go with a Magnaflow cat. We don't have any inspections in Indiana, it's like THUNDERDOME!!!

Title: Lost Cat (converter)
Post by: jeingold on November 13, 2006, 11:12:10 PM

I just installed the Dynomax Super Turbo Muffler with a straight 2.5 inch pipe (no cats).  I think it sounds really good.

At first I tired a 2.5 inch pipe and the stock muffler (no cats), but that was raspy.