PersianEVO

iTrader: (3)

I am really stuck on whether or not to run a race pipe or high flow cat? How big a difference is the power? Is it worth the hassle? Would my mitsu dealer be more annoying with a catless car or would a high flow cat basically get the same reaction. Does running a catless car have any negative effects on the vehical long term? Does it make my car smell bad on the inside?? Thanks for any feedback!

OliSim

iTrader: (2)

Greetings,

I run my EVO without a cat with no ill effects. I've heard that the cat delete provides about 10hp with proper tuning after the change. No adverse smell in the car, but it does smell "good" from the outside. I have not experienced any ill effects other than a great disparity in fuel mileage. Driven hard, my EVO can get less than 10mpg, but driven economically can provide 27mpg.

My car has full exhaust, cams, intake, piping, throtte body and Works P2 Flash with Cam tune. It runs great!!!

OS

simevo

iTrader: (1)

Going catless makes the car much louder and you might get CEL.
HP difference is not much compare to the Helix HF cat which uses the metal internal cat instead of ceramic.
But Cat delete will always give the best power on the top-end by small amount.
Plus if you ever get caught by the police, you don't have to worry as much if they ask and look under the car.

JaguarS4R

so High flow cat is overall the way to go??

Bom's Evo

iTrader: (14)

w/o a cat is definitely louder. you also get more fumes.

but its much more power. period!

TrustWRX

All your cats are belong to the floor in your garage or in my case my bedroom floor. (well at least that's where my entire stock exhaust is).

vletnguyen

iTrader: (26)

i am thinking about going catless myself.. my hiflo random cat throws cel anyway.

negativeB

iTrader: (1)

cat-delete in some states is illegal. i think the minimum fine for running catless in cali is $2000. but you can backfire with no cat. =j

JaguarS4R

and flames, seriosly, all my CATLESS buddies shoot fire, so in order to shoot fire, I must get rid of the cat and just have a straight 3' turboback?

evo81

iTrader: (30)

don't be a pansy.go catless.more power. .if your worried about smog or something,just switch it out to stock.only 4 bolts

GREDDY

iTrader: (8)

People with about the same mods as I do, that are running catless, are dynoing about 10+awhp/tq more then me. If your going to be running catless, I wouldn't suggest Buschur exhaust, it's pretty loud compared to other exhaust I've heard. The Buschur exhaust is awesome and proven more powerful but way to loud w/out cat. That's why I got a cat on my Buschur. Even with the cat in, it's pretty loud. When I get home early in the morning (4am), my neighbor normally tells me he can hear my car from far away and I even try to stay under 2k rpm once I enter my neighborhood.

Bom's Evo

iTrader: (14)

if your going to mix match stuff. a UR cat delete is awesome. no CEL

meanmud

iTrader: (74)

I keep throwing the P0300 code; however, I have never thrown an O2 code. Being catless is enhancing the "Certain" harmonic frequency causing the P0300

o3evo8

iTrader: (2)

I'm running the UR hi flow cat and perrin d/p and c/b, prior to changing my exhaust (stock) i had P0300 codes all the time now since i've changed it out nothing at all not one code and its been 4500 spirited miles

EVOeight

CATless will reduce back pressure, reduce weight, increase noise, reduce muffler temperature, increase gas mileage, increase hydrocarbon emmisions, and cost less than a high flow CAT...