serin

iTrader: (2)

ok, i have a P0430 code, "catalyst inefficiency, bank two" that won't go away. i'm told by several that it's an o2 sensor in the precat, which of course i have cuz i'm cali spec.
for the cost of diagnosis, and fix, i realized that i could get a y-pipe, and be gone with the 02 sensor altogether. if that's so, what exactly do you do with the o2 sensor?

also, this is now my wife's car, so i don't want it to be too loud. i'm planning on keeping the stock muffler, will that negate the power of the y-pipe?

thanks guys.

upstatemax

iTrader: (15)

The o2 sensor has to stay on the car...

You have two options:

1- re-locate the sensor behind the main cat in the B-Pipe

2- Simulate the sensor signal with an O2 simulator (what I did)

With the simulator you have to keep the sensor on the car, just dont have to put it on the exhaust. Just tie it up somewhere in the engine bay.

Edit: the stock muffler will not negate the power from the y-pipe. I use one with my headers, I put it back on after a Cattman muffler and I felt no difference in power; it was just not so damn loud...

ctrent86

Are all O2 sims the same? Recommend any?

upstatemax

iTrader: (15)

This is where I got mine from:

http://www.o2simulator.com/

blackpearle

upstatemax, were the headers worth the $$?? I'm trying to figure out if the headers are worth the extra or to just go with a Y-pipe instead.

Hoooper

for a 2000-2001 its not REALLY worth the money unless youre planning to go for serious power. a y-pipe will give you reasonable gains and the headers only give a little more.

MaxBoost925

iTrader: (33)

naw man, for 5.5 gen headers will give you very high gains. y-pipe does very little.

for 5.0 gen, headers will give more power than y-pipe as well.

steven88

iTrader: (28)

a cattman ypipe on a vq30de-k would give some nice gains....a cattman header on a vq30de-k would give some nicer gains...any questions?

upstatemax

iTrader: (15)

Yes, I might be selling them soon as well...

Time for a change.

Hoooper

thats what i said...didnt say anything bout a 5.5gen

blackpearle

Guess I need to clarify, my I35 is an '03 model.

Teufelhunden

iTrader: (8)

no mean to hijack, but would you lose low end, if you get y-pipe on a 5.5? would that affect much on city driving?

SinCityMaxPower

No ,with the Y you gain power acrross the whole powerband

sloppymax

iTrader: (8)

this is mostly true for the 3.0 but the gains for a y pipe on a 3.5 are minimal. there are a few dynos where it would not justify the cost of the y pipe and install time/cost for a 3.5 in my opinion. i would consider a y pipe for a 3.0 but not for a 3.5 based on concrete dyno info.

NewLoveI30

Headers will provide most power if you have either a VQ35 or a cali spec VQ30. The y-pipe still leaves the front pre cat in place if you are Cali spec. Headers will get rid of the front precat in addition to other benefits.