tnhunter2

I'm looking at getting either a high flow cat or test pipe. I'm unsure which way to go. I have found brands of both that have a connection for the 02 sensor so that way it should not throw a code. Had anyone used one of those and still had a code thrown? I'm an Evo newbie, that's why so many questions. Only been an owner for 3 months. : )

Tpatterson

iTrader: (1)

Either catted or catless CAN throw a code. Just because there is an 02 bung does not mean that a test pipe cannot throw a code, it still can, even with a defouler. Only real way to ensure that you don't get a cel is to get the cel disabled when you get a tune. (unless you can't do that on these cars, correct me if I'm wrong, haven't gotten tuned yet).

tnhunter2

I'm pretty sure you can disable it when you have it tuned.

On a side note, has anyone got any experience with those all in one down pipe/test pipe things?

codgi

iTrader: (22)

This and yes you can disable the codes using ECU tuning.

ThatMileHighEvo

test pipe

PatricksEvilEvo

iTrader: (12)

I say just get a high flow cat. There really isn't a benefit to a test pipe over a high flow cat, I don't care what anyone says. Unless it's a track only car, get a cat.

PatricksEvilEvo

iTrader: (12)

I see this as more of a pain in the a** than anything, I have a Megan downpipe, stm test pipe and Buschur scca cat-back and I'm happy but if I was going to start again, for street use I would have bought a Buschur cat instead of the tp.

BlazinVIII

i think i'd go with a high flow cat since the evo is already enough of a cop magnet as is (even when stock).

Thore

iTrader: (27)

I have had both HFC and test pipe on my car. There is a difference between the two and its pretty apparent. Since I live in an area that doesn't have emissions, I knew I could get away with just a test pipe. That may or may not apply to you.

I was tuned with HFC installed. For S**ts and giggles I installed my test pipe and noticed a decent increase in power and quicker spool. The exhaust was a bit louder and more aggressive sounding. The exhaust will tend to smell more now and if cruising on the freeway, the person behind you will probably wonder why his eyes are all of the sudden burning. Your wife will start to complain that you smell like exhaust. The cloud of unburnt fuel will be more obvious when you WOT.

Throttle

iTrader: (1)

i ordered a high flow cat. i wanna keep the noise and the exhaust smell down.

CrazyLilPunk

iTrader: (3)

test pipe

Whats the point of going high flow cat? Its more expensive, it may make your car smell a little better, but it wont safe the enviroment or consistently keep you from throwing a CEL. And although the high flow cat might act as a muffler, its an Evo, you're expected to make big boy noise

daonlyillwiz

test pipe, bbecause either way you will throw a code. You can get one of those o2 sensor bungs that go into the existing o2 sensor to push the sensor further away from the exhaust to not throw a code though its not 100% guaranteed it will work.

get DSMLINK and you wont have to worry about codes

killerpenguin21

iTrader: (20)

hi flow cat hands down. i had a "resonated test pipe" and my ears would ring after a highway drive. hi flow quited it down considerably, no more stained bumper, no more smell, 49 state legal, no CEL etc.

also, lost next to no power. 10 ft/lbs...maybe.

okevolutionVIII

iTrader: (71)

I'm thinking about going to a high flow cat myself. After first installing a testpipe back in '05, the exhaust had this raspy, loud note to it that I never liked with anything other than WOT.

On my new build, I went from a test pipe to a resonated test pipe and it still has this note that I can't stand especially driving around town. I've considered STMs aluminum bolt on muffler but they seem uninterested in selling any after multiple request from several members for sound clips with no response.

evodriver49

iTrader: (6)

milspec hfc ftw! its like 100 cell hfc so it flows very well. i made ~380whp on a dynojet with the stock 9 turbo and my tuner said with my bolt ons (kelford 272 cams, injen intake, 3" exhaust, 3"ic, uicp, licp, o2- @25 psi) thats exactly where i should be at even with a test pipe. im sure a tp will flow better with a larger turbo but im way content with my hfc being able to reduce a lot of smell and nasty smoke ESP because im in southern california where the cops HATE smelly cars. (:


and also when i had cams and intake and exhaust with my initial tune i only made 323whp @25psi BECAUSE i had the stock cat.