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Cat or Muff by steve308
Started on: 07-22-2013 12:56 PM
Replies: 18 (477 views)
Last post by: 1fast2m4 on 07-27-2013 06:30 PM
steve308
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Report this Post07-22-2013 12:56 PM Click Here to See the Profile for steve308Send a Private Message to steve308Edit/Delete MessageReply w/QuoteDirect Link to This Post
2.8 86 with auto ----- Looking to "improve the sound" during the redo of the OE exhaust system on car. Emissions are not an issue --- which "delete" gives a better sound that is not to loud or droning. Out with the cat (straight pipe) and just use a stock muffler or the opposite -- keep the cat and muffler delete -- or muffler in place of the cat. I am not interested in an aftermarket system.

Thanks in advance
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Shonyman32
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Report this Post07-22-2013 01:01 PM Click Here to See the Profile for Shonyman32Send a Private Message to Shonyman32Edit/Delete MessageReply w/QuoteDirect Link to This Post
I would not delete the muffler.

I have deleted the cat and my neighbors complain if I leave past 11 o'clock at night because its loud. (I think my muffler has a lose baffle as well)

Although with hard acceleration the car sounds pretty good in my opinion.
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steve308
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Report this Post07-22-2013 03:10 PM Click Here to See the Profile for steve308Send a Private Message to steve308Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Shonyman32:

I would not delete the muffler.

I have deleted the cat and my neighbors complain if I leave past 11 o'clock at night because its loud. (I think my muffler has a lose baffle as well)

Although with hard acceleration the car sounds pretty good in my opinion.


Did you straight pipe it or put a glasspack in place of the Cat? Neighbor goes to work at 5 AM and has a Harley ---- I don't think he would have grounds to complain
if I made just a bit more noise

[This message has been edited by steve308 (edited 07-22-2013).]

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armos
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Report this Post07-22-2013 09:42 PM Click Here to See the Profile for armosSend a Private Message to armosEdit/Delete MessageReply w/QuoteDirect Link to This Post
I had a rotted, leaking muffler on my 86 2.8 Auto. Cat was still there, but it was starting to fail also. I don't know if it was enough to affect the sound.

There was a tipping point when the muffler suddenly was leaking badly and became very loud. It was loud enough that I felt like an annoyance. I was consciously trying not to load the engine in residential areas at low RPM because of the loud droning noise. I'd downshift on hills, but I'm not sure that helped the volume any.
Under hard acceleration through the whole RPM range, yeah it was loud but the quality of the sound was worse IMO.
The only thing I liked better with the leaking muffler is that on deceleration it had a nice burble to it. The muffler ruins that.

I did later find that my catalyst was coming apart, so maybe that was a factor in how it sounded. In your case, assuming muffler fully removed and a completely good cat, maybe it would sound better than mine did, I really don't know. All I can say is that when my muffler split wide open, it sounded like ass. Not quite fartcan Honda territory, but it's pushing that direction. Volume was also too much, it was definitely too loud for driving at night near houses, and I'm sure I would have been awarded a noise ticket before long.
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1fast2m4
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Report this Post07-22-2013 10:29 PM Click Here to See the Profile for 1fast2m4Send a Private Message to 1fast2m4Edit/Delete MessageReply w/QuoteDirect Link to This Post
The sound will change for the louder if you delete the CAT, It would be VERY VERY loud if you delete the muffler. I'd start with the Cat delete, it's easy enough, just about 18" of pipe.

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1986 SE 3800SC/4t65eHD (12.871@104.96) I'll Sell it if you like
1985 GT 3800SC (swap in progress)

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AL68
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Report this Post07-22-2013 11:23 PM Click Here to See the Profile for AL68Click Here to Email AL68Send a Private Message to AL68Edit/Delete MessageReply w/QuoteDirect Link to This Post
Deleting the converter will make it louder. I'm fixing up an 86 GT for my daily driver, the previous owner removed the converter, it sounded loud & raspy. I put on the longest 2" glasspack I could find in place of the cat, had about 25" of room. It sounds a lot better now, more of a quieter/lower rumble.
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Lou6t4gto
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Report this Post07-23-2013 01:00 PM Click Here to See the Profile for Lou6t4gtoClick Here to Email Lou6t4gtoSend a Private Message to Lou6t4gtoEdit/Delete MessageReply w/QuoteDirect Link to This Post
If you delete the cat, put in a glasspack (25" long, 2" in/out) advanced has them for $23. straight pipe is loud and will give you Backfire noises under DE-celleration.
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steve308
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Report this Post07-23-2013 01:22 PM Click Here to See the Profile for steve308Send a Private Message to steve308Edit/Delete MessageReply w/QuoteDirect Link to This Post
Thanks to all -- glass pack in place of cat sounds like the way to go.
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I FAR I
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Report this Post07-23-2013 03:53 PM Click Here to See the Profile for I FAR ISend a Private Message to I FAR IEdit/Delete MessageReply w/QuoteDirect Link to This Post
IMO an 18" Vibrant resonator in place of the cat is better sounding and will last longer. Combine that with resonator exhaust tips and your car will sound very nice.
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steve308
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Report this Post07-23-2013 06:33 PM Click Here to See the Profile for steve308Send a Private Message to steve308Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by I FAR I:

IMO an 18" Vibrant resonator in place of the cat is better sounding and will last longer. Combine that with resonator exhaust tips and your car will sound very nice.


Did you use the standard or ultra quiet and if what I am seeing in the catalog it looks like 2 1/4 is the smallest size inlet/outlet pipe. Were you able to clamp it directly or did you need to add additional pipe (I have not climbed under the car to measure the cat size) or did you have it welded on. I like the look of the product over the standard glass pack. Do you happen to have a picture of the install?

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Report this Post07-23-2013 07:17 PM Click Here to See the Profile for Lou6t4gtoClick Here to Email Lou6t4gtoSend a Private Message to Lou6t4gtoEdit/Delete MessageReply w/QuoteDirect Link to This Post
How much do the resonator "TIPS" actually quiet it down ? I'm looking for Silent from a 3800SC
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1fast2m4
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Report this Post07-23-2013 10:07 PM Click Here to See the Profile for 1fast2m4Send a Private Message to 1fast2m4Edit/Delete MessageReply w/QuoteDirect Link to This Post
................

[This message has been edited by 1fast2m4 (edited 07-23-2013).]

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1fast2m4
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Report this Post07-23-2013 10:09 PM Click Here to See the Profile for 1fast2m4Send a Private Message to 1fast2m4Edit/Delete MessageReply w/QuoteDirect Link to This Post

1fast2m4

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My car without the resonated tip sounds like ASS!!! I only have a single 3" with a 18" Jegs glass pack (Magnaflow) with another 9" of 3" resonated tip.

with and without the resonated tip is a huge difference, if you want quiet use as many resonators at you can.

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Report this Post07-23-2013 10:21 PM Click Here to See the Profile for dobeySend a Private Message to dobeyEdit/Delete MessageReply w/QuoteDirect Link to This Post
Keep both, and get the Pacesetter cat-back system, and use the C6 Corvette tips.
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steve308
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Report this Post07-24-2013 11:14 AM Click Here to See the Profile for steve308Send a Private Message to steve308Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by 1fast2m4:

My car without the resonated tip sounds like ASS!!! I only have a single 3" with a 18" Jegs glass pack (Magnaflow) with another 9" of 3" resonated tip.

with and without the resonated tip is a huge difference, if you want quiet use as many resonators at you can.


I was behind 1fast2m4 on the way to Carlisle - (3800SC) When he gets on the fun pedal you know he has left the building!

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I FAR I
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Report this Post07-24-2013 10:59 PM Click Here to See the Profile for I FAR ISend a Private Message to I FAR IEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by steve308:


Did you use the standard or ultra quiet and if what I am seeing in the catalog it looks like 2 1/4 is the smallest size inlet/outlet pipe. Were you able to clamp it directly or did you need to add additional pipe (I have not climbed under the car to measure the cat size) or did you have it welded on. I like the look of the product over the standard glass pack. Do you happen to have a picture of the install?


Standard, clamped to downpipe...I had a cat delete set-up initially with straight pipe, but cut the pipe and put the Vibrant resonator in place of the cat....sorry no pics, but it was done quick and easy at a local garage.
The 18" Vibrant cuts out any drone and sounds real smooth yet sporty with Flowmaster 40 muffler...The ANSA/Pacesetter style resonated tips accentuate the sound just right...sound at cruise speeds is mellow and sporty, but when I stomp the throttle it 'barks' and sounds real sweet.

[This message has been edited by I FAR I (edited 07-25-2013).]

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Report this Post07-25-2013 04:38 AM Click Here to See the Profile for uhlanstanClick Here to Email uhlanstanSend a Private Message to uhlanstanEdit/Delete MessageReply w/QuoteDirect Link to This Post
Never install the muffler in place of the cat,, this hurts performance
always install the muffler as far back as possible,this helps performance
glasspacks hurt performance,has to do with the many small inlet/outlet perforations
but glasspacks are cheap
try to avoid install muffler in cat location,just place a straight pipe where the cat was
a dynomax super turbo muffler will add horsepower ,increase MPG & will fit
the glass pack is the easiest install ,but thay all hurt performance
always cut muffler out ,leaving as much tail pipe as possible .
hardware store has L & T brackets,,turnbuckles that ease install
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steve308
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Report this Post07-27-2013 05:45 PM Click Here to See the Profile for steve308Send a Private Message to steve308Edit/Delete MessageReply w/QuoteDirect Link to This Post
Just thought I'd follow up --- I took a few measurements - bend to bend on my 86 I could not get a 25" glass/pack into the space - it appears that the max length available to me is about 20 inches in total of a straight run. I will have to shop for a shorter glass/pack or go with the 18" resonator option, however, the physical inspection of the cat and the lack or exhaust exiting the tail pipes led me to believe my cat was clogged. After removing the rotting and rusted heat shield a light tap on the converter confirmed that it was. A couple of firmer hits dislodged the "clog" (aka gutted the cat) which has resulted in the nice mellow tone I was looking for. (and a restoration of missing power). If I can't find a down pipe in a pick and pull over the next couple of weeks to attach a glass/pack to I'll most likely do the straight pipe and be done with it. As an additional benefit it sure will make getting to the starter and oil filter easier!
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1fast2m4
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Report this Post07-27-2013 06:30 PM Click Here to See the Profile for 1fast2m4Send a Private Message to 1fast2m4Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by steve308:

I was behind 1fast2m4 on the way to Carlisle - (3800SC) When he gets on the fun pedal you know he has left the building!


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