[Dak4life]

I have no secondary cat (one under the cab of my truck) i got a flowmater 40 series and its dumped right after. right now w/o the cat is super loud but sounds mean, would a high flow cat be worth putting on performance wise? and would it quiet it down a bit?

 

[viperkota]

being high flow it will still help with the performance and it will quiet it down a bit.

in mine i did have 2 gen 2 viper cats and no mufflers. it was pretty darn quiet till you got on it.

 

[addicted2blue00]

unless u gotta have it on there for emission inspection bs i wouldnt waste my time, to my v6 it was louder n didnt help but now im glad i did cuz my 360 like to breathe, it needs a bigger exhaust so imma cut the muffler off before takin it to the exhaust shop, i also have my after cat o2 in the frame which help keep the cel out

 

[Hustlajustin]

Ive seen some guys put on hi flow cats and GAIN low end vs. not having one at all...

I have a hi flow magnaflow cat.

 

[Dak4life]

w/o my secondary cat i dont throw a code. i just put a pipe where the cat used to be. there is an o2 sensor but no codes are thrown. and so be honest it smells like shit when u first start it up due to the unburned fuel haha. i got a high flow on ebay for cheap so i think im gonna put it on to make that smell go away. smells like an old carb engine kinda

 

[durangokid]

my buddys v6 stang had a offroad x pipe, and flowmaster cat back and it was INSANE loud
2 high flow cats and now it just sounds MEAN!!

 

[Bos-R/T]

My old setup I had two factory cats and 2 40 series delta flow flowmasters.I bought 2 high flow magnaflow converters and mine got more louder.Like a deeper growl to it.And it sounded like a damn race car when you snapped the throttle.It reminded me how that charger sounded on too fast too furious.When the american muscle comment came in.It sounded mean.A huge noticeable difference in the high flow with sound.With factory cats you are losing noise resonance.the higher flow cats dont muffle out the sound that the factory cats do.Im sorry if someone says they quiet the exhaust down.Thats entirely untrue.Mine was a considerable amount of sound difference.I was extremely pleased.

 

[Bos-R/T]

And with the high flow I noticed a small amount of better throttle response.

 

[durangokid]

they quiet it down from not having a cat is what we are stating
most people just remove them and then go to adding them back.

 

[Bos-R/T]

He says he has no secondary cat

 

[Dak4life]

I have NO secondary right now. thats y i was wondering if i should even put a high flow on because im not throwing a code and its loud as shit and sound pretty good

 

[durangokid]

yea like I said
if U add a high flow where the secondary was, it will quiet it down
if u replace the OTHER cat with a high flow cat, it will get louder

Volume gauge quieter<louder
Stock<highflow<none

 

[Bos-R/T]

yea like I said
if U add a high flow where the secondary was, it will quiet it down
if u replace the OTHER cat with a high flow cat, it will get louder

Volume gauge quieter<louder
Stock<highflow<none

Yep

 

[Dak4life]

thats the only cat i have under the truck. the other 2 come right off both manifolds and are the size of my fist they are tiny. im not going to mess with those

 

[viperkota]

thats the only cat i have under the truck. the other 2 come right off both manifolds and are the size of my fist they are tiny. im not going to mess with those

you will be fine with just the 2 cats...my wifes 4.7 has them just after the manifold as well, but never came with a third cat. just find a nice muffler.

 

[Dak4life]

i got a flowmaster 40 series on there

 

[Gbone1113]

being high flow it will still help with the performance and it will quiet it down a bit.

in mine i did have 2 gen 2 viper cats and no mufflers. it was pretty darn quiet till you got on it.

Did you notice an increase when you added the viper cats?? Where did you get them from? And why did you go with the viper Hiflows?

 

[radioactive]

Did you notice that post was from 2009?

 

[Gbone1113]

Did you notice that post was from 2009?

Did you notice that “you’re not that guy” that I was asking??

 

[radioactive]

In fact I did.

The guy you were asking is banned from the forum, according to the word "banned" under his moniker. So the likelihood that you are going to get a response from a 12 year old post by a banned member is zero. But perhaps someone else with similar experience will see your question and chime in.