Exhaust/Mufflers

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Doppleganger

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I live in the city, so I have to run cats under my truck.
I will be using a set of Jones Exhaust Flow Pack Mufflers model JFP300 for the 3 inch size.
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https://www.summitracing.com/parts/jex-jfp300/

They are basically a cherry bomb shape single chamber muffler.
This should keep it rumbly with the highflow cats I have to put under it as well.
If not, we may just have the cats under it depending on how it sounds.

Right now it has stock manifolds to a crappy 2.5 inch set of pipes that rotted off in front of the axle.
I found a set of Flowmaster tailpipes with 2 chamber mufflers and put them under there.
It is pretty quiet for what it is....

Ever use a Catco free flow cat? When I resto'd cars I always added them in the event anyone who ever owned it HAD to have them...was the next best thing to not having one at all. I dont have to have them on mine but have still used them for any drone issue. Worked better than an official resonator and was cheaper too.

My truck is getting a new 3" with long headers and (leaning towards) a couple of MagnaFlow mufflers. If it has any drone I might think about trying them with it.
 

RoryH19

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I run cats on all my cars. After 25 years old only need to pass a safety inspection.
I use high flow magnaflow ones. Would be hard to tell if I'm loosing any HP.
Plus as mentioned it cuts down on the smell and of course helps the environment : )
These on on my dual exhaust LS 6.0 k5.

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78C10BigTen

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I run cats on all my cars. After 25 years old only need to pass a safety inspection.
I use high flow magnaflow ones. Would be hard to tell if I'm loosing any HP.
Plus as mentioned it cuts down on the smell and of course helps the environment : )
These on on my dual exhaust LS 6.0 k5.

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Wish my trucks underside was that clean
 

Doppleganger

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Youd think MI that would cause rust faster then PA

I think you have that magnesium chloride sht some mad scientist created. My buddies son is a Ford tech in Pittsburgh - said they had 4 yr old Taurus's coming in with rotted out steering racks (but I thought that was stock?). lol

Not sure who all is still using it but last I heard the state DOT's were screaming that its eating the bridge's up too. Meh....as long as some plutocrat makes a buck, they'll find an excuse for it.
 

RecklessWOT

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I do not understand why some folks are so down on catalytic converters. Obviously I know that they create some amount of flow restriction, but high flow cats aren't bad. I live out in the country, I do not need to pass any kind of inspection or emission test. What i like about cats is that my exhaust smells better, and the muffler and tail pipes will last longer. Think about the amount of money some of us have in our mufflers, cats help protect them. Just my opinion and I wanted to through it out there, if you have to run cats, or want to there is a benefit. Thrush mufflers in general are pretty good and cost a lot less than other brands. I'd run them without a second thought.


Well, yeah exactly, they cause restriction. High flow cats flow better than regular cats, but not having a cat at all flows even better. Plus it's a hell of a lot cheaper to just remove them, a 2 foot section of straight pipe does not cost nearly as much as a high flow cat. IMO it sounds better without them, and the smell does not bother me one bit, I would actually argue that my exhaust smells better without cats. If I was at all worried about the way my exhaust smelled I would not be driving a 30+ year old truck with a v8 in the first place...
 

Shorty81

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I think you have that magnesium chloride sht some mad scientist created. My buddies son is a Ford tech in Pittsburgh - said they had 4 yr old Taurus's coming in with rotted out steering racks (but I thought that was stock?). lol

Not sure who all is still using it but last I heard the state DOT's were screaming that its eating the bridge's up too. Meh....as long as some plutocrat makes a buck, they'll find an excuse for it.
My county in Ohio uses that stuff aka "beet juice". That's the reason I put the bike up early. Used to ride deep into December, but one year that stuff rusted my brake disk, caliper and all lower bolts. Worse than salt ever was. Major reason for this crap is the litigation crazed drivers who sue it they slide off road. They spray this crap in advance of inclement weather. It actually scars the asphalt over time. Brake lines rust out quickly.
 

bucket

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My county in Ohio uses that stuff aka "beet juice". That's the reason I put the bike up early. Used to ride deep into December, but one year that stuff rusted my brake disk, caliper and all lower bolts. Worse than salt ever was. Major reason for this crap is the litigation crazed drivers who sue it they slide off road. They spray this crap in advance of inclement weather. It actually scars the asphalt over time. Brake lines rust out quickly.

Yeah, it's nasty stuff. I hate that crap.
 

SirRobyn0

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Well, yeah exactly, they cause restriction. High flow cats flow better than regular cats, but not having a cat at all flows even better. Plus it's a hell of a lot cheaper to just remove them, a 2 foot section of straight pipe does not cost nearly as much as a high flow cat. IMO it sounds better without them, and the smell does not bother me one bit, I would actually argue that my exhaust smells better without cats. If I was at all worried about the way my exhaust smelled I would not be driving a 30+ year old truck with a v8 in the first place...
Please don't take this as trying to start an argument I'm really not I promise. I don't dispute that there are benefits to going without cats, but I do want to comment a little further on the smell factor. A well tuned engine that doesn't burn oil will have less odor at the tailpipe with a cat than without. An engine that is burning oil or is excessively rich or lean will often have a sulfur smell at the tailpipe with a cat, rather than smelling like burning oil or rich exhaust. Oxides or Nitrogen (NOx) is an odorless gas which all engines produce and it is really good at destroying lung tissue, cats cut down on this dangerous gas considerably. Hey it's all up to the individual and what they choose to do and that's fine. :)
 

Catbox

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How well do those Flowmaster tailpipes fit? Does it look like they would clear a rear mounted fuel tank?

Whelp.
I can only imagine they fit the stock application they were made for like a glove.
Since my set is made specifically for a Fox body Mustang, they had to be made to fit our truck.
My son put them under the truck so they would clear everything with out chopping them up as I told him not to cut them.
He did his best wrestling job up in there to make it work on a PER-TEMPORARY basis until we get the new exhaust for it.
He put them under it by swapping side to side and that put the tailpipes right in the center of the bed.
Looks weird, but works like a champ.

I found a great deal on these mufflers and could not pass it up...

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Here is junior and his craft.
We even got to use some super cool flex pipe in there to connect the new to old stuff...

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Catbox

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Ever use a Catco free flow cat? When I resto'd cars I always added them in the event anyone who ever owned it HAD to have them...was the next best thing to not having one at all. I dont have to have them on mine but have still used them for any drone issue. Worked better than an official resonator and was cheaper too.

My truck is getting a new 3" with long headers and (leaning towards) a couple of MagnaFlow mufflers. If it has any drone I might think about trying them with it.

I haven't used that brand specifically, but I have used a few high flow cats.
Our 1995 Suburban has a high flow under it with a 3" two chamber Flowmaster and it sounds good.

I have been looking at the Magnaflow cats from Summit to replace the ones under the truck.
 

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