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No cats + open cut out = holy crap

9.2K views 53 replies 22 participants last post by  radocrazy07  
#1 ·
Ummmmmm yeaaaaaaaah...


So if you read my howto on the 2nd cat delete.. or I told you.. I no longer have ANY cats on the truck..

So today I wondered what it would sound like, ITS. FUCKING. LOUUUUDDD, WAY louder than it was with the cat on it.. too loud actually...

Also, it seems like its lost a LOT of low end torque im guess cause it lost so much backpressure..

heres a short clip.. dunno if the sound will come out right or not.. its WAY louder:

 
#4 ·
lol cmon man, you know better, re read! CUT OUT open lol ive got a exhaust cut out before the muffler.. so technically its straight pipe lol

NO cats + stock muffler with turndown is still very quiet with a cool tingy sound to it..

hahaha, thats loud as a motha' you need to close that cut out dude!
im going to..


Sucks tho, my cut out was fun before.. its kinda pointless now :(
 
#10 ·
says the guy with "too many mods to list" and a "fully built 3.5" that runs 15.7's :lmaop:

JFWY :high5:











yeah im waiting for it to cool off, since its so low and cant see I have to feel around to put it back on and I burnt the crap out of my hand earlier :lol:
 
#16 ·
yeah, a LOT of loss low end.. if I can ever find the fucking cord you'll see..



gain any with the cutout closed? I wasthinkng about taking all the cats off and running just a 3" pipe with a flowmaster or something dumped right at the cab
no cats.. with the cut out closed, yea ir was a gain losing the 2nd cat
 
#15 ·
dont think ill be leaving texas for a meet of 20-30 trucks when i have a 30min drive to a meet that i organized with 130+ trucks and 60% of those truck run 12s and better.


sponsored by best buy with dj and brake dancing and madden turnoments??


no thanks :lol:
 
#19 ·
hmmmmm see cause im debating after the JTR headder to do a full 3" exhaust with highflow cat to a borla or magnaflow.....


but this makes me kinda not want to do the high flow cat :lol:
 
#20 ·
I had a cut out before the 2nd cat coming right out of the headers basically and it was INSANELY loud.
 
#23 ·
2 cell phone videos..

Ive got video on a real camera.. but still cant find the FUCKING CORD!!!! :hulk:



NO CATS + Factory Muffler w/ turndown: (cut out closed)


NO CATS + Cut out open:
 
#27 ·
what? engrish please

sounds like your hot rodding that truck ha alot of gurgle
lol yeah it does that sometimes when you crank it, kinda lopes for a minute, just happened to do that in both videos lol
 
#31 ·
Not sure, forgot to try it out at the track, I ran it with the cut out open when it still had the cat on it.. and it was about the same..

Now I dunno, its WAY loud and loses a lot down low, but pulls very well up high..

I dont really even open it, before the cat was removed it was a cheap way for my truck to be louder, then if I wanted it quit I could just close it.. now its too loud so I dont really open it.. I might get a real exhaust system someday lol

sounds great,have u notice,your fuel consumption,gain or loss?
Not really, besides getting throttle happy because its REALLY responsive with no restriction its a little worse id guess, but not much

you know damn well thats killing his mpg with the cutout open. must be runnin rich now...

ricky, arent you just tuned for the rev limiter and tc?

actually, with the cut out open I can run 90-100mph on the interstate and it gets AMAZING MPG.. its weird, but overall yea it probably hurts it some..


Tuned is not the word I would use to what we did, with some wisdom from jackedupcanyon we just removed T/M (which did NOTHING :hulk:) and raised my shift points.. which are too high and probably slowed it down because it revs too high sometimes and we didnt tune anything on the tranny, fuel trims or anything like that, its all 3.5 stock stuff.. and removed the speed limiter..

honestly I wish we had just left everything alone and only removed the limiter

Im trying to find an 07 3.7 PCM to put in it and start over
 
#29 ·
sounds great,have u notice,your fuel consumption,gain or loss?
 
#33 ·
Money man.. thats purely it.. It needs a tune. SO. BAD.. but its gonna be 400-500 and I just never have that.. fuckin BLOWS :(


Yeah, thats why I dont open it anymore really.. and another reason why I dont even have an aftermarket exhaust lol I like my truck being quiet, unless I get on it, then you just hear intake..
 
#34 ·
I have no cats and mbrp and once the torque converter clutch locks up she gets pretty quite til I stomp it then it roars like a mad beast and scare ppl like crazy and I need a few more bolt ons and a tune and I am poor like you wtracing so you aren't the only one