Well i was driving around last night night and just at one instant my car got incredably load ( my friend told me i sound like very other ricer, not cool). i know its the cat cause i can see a huge rust hole in the side of it. is there anything i can upgrade it with, like a test pipe?

 

if there is no e-check in your county, then sure you could kill the ozone with a test pipe. otherwise just get a kitten

 

hi flow cat... or just have taken out (you'll have to do this yourself... no regular shop will do this for you)

 

Upgrade1: Weld a piece of metal...

Upgrade2: Replace with a 2hole cat ...

 

They sell a tape that you can wrap around it that gets hard, its not the best route to take but if your looking for a cheap way out it'll work for a little.

 

That stuff actually works as a temporary fixed. I've used it to help sell a car

 

I don't have a hole in my cat but when I removed the y-pipe I noticed that all of the stuff inside was busted up. I could reach in and scrape alot of it out into the driveway. Anyways, I live in Tennessee and we don't have anything close to emission checks here. Most of the time I would say to just put in a test pipe but has anyone here tried that? How is the sound? I know it will get louder because when I removed the cat on my z28 my neighbors quit talking to me. If it doesn't sound too ricey then I will do that if it will save some money. I already spent all I have fixing everything else that is wrong with the car.

 

God you have to love the lack of emission laws there. That's why I'm keeping my truck registered there no matter what base I go to. That way if I get stuck somewhere like Cali.... I can go "FU... my truck is registered with TN, and I don't have to do any checks"

 

are you sure it's the cat and not the flex pipe?

 

If you are talking to me, yeah it is the cat, when I removed the y-pipe from the cat I could reach inside the cat. To be honest, would a clogged cat cause the honeycomb inside to break apart or do they just do that over time?

 

if the test pipe is welded in good, and all other exhaust is in good condition, its not nearly as loud as you would think

 

Yes buy any muffler (with only 2holes) that fits in. Maxima does not need cadmium to enviro leaching catalyzator: cat is only because of the bribed greenpiss pleasing legislation. Your pwr output will also increase (5-15%).

 

a properly functioning catalytic converter will NOT hurt your horsepower output at all.

if the honeycomb has started to break in your cat, then the car either has or had another problem (i.e. running rich for too long, head gasket leak, oil burning, etc.)

 

referring to the orig poster

 

Wha? Are you saying cats don't do anything?? You are kidding right? Cats do work.

 

http://auto.howstuffworks.com/catalytic-converter.htm

 

but a cat reduces exhaust flow, right? why else are there hi-flow cats? that would mean a bit of a hp loss, correct?

 

They don't have the same air polution laws as we do

 

it means that people are suckers.

 

Cats catch mice, thats the only proper work they do.

In cars, they do evil work: spread cadmium [and other heavy metals] into enviro. The secret that is not to be told is that cadmium levels jumped sky high in southern sweden when cadmium filled cats started to arrive in 90's...
Also, cats without mice rob performance.

 

So you have some airflow testing to prove this correct?

 

Pwr.: No. On this issue its only secondhand storytelling: I just believe what I've read. For me, these (multiple) stories of cat increased backpressure sound reasonable. I'd think this could easily proven to be true/hoax with a dyno...

Then theres also the q of New vs. Ol cloggiecats [=cat with only one hole].

Cadmium in enviro: Science arTicles, happen to believe those also wihout proof.

So what do I no...u

 

I've seen dynos here that removing the cat on a na maxima did close to nothing. Even hurt performance. Of course if it's clogged up, sure. But performance cat vs a good cat vs no cat = even all across the board.

 

I take your word on that. Still, as the engine system is an entity where out cannot come more that is put in, other ppl's experiences on other settings (other cars) may be like as they claim.

Can u say is there anythin common (intakewise) on those maxes u refer to? Mods, turbo, whatever...

 

Wiking... our cars don't put out enough for the cat to effect it. Now on a V8 or Turbod V6. you might run into enough for it to loose a small amount of performance.

 

...this means that if i throw current ALU-intakes out, put directly six 50mm flaps to control air input, I get 300hp...[MAF aside]

(Btw. MAF is 'just crap nuisance'. If Citroen 1.8i has none [I know it has NOT], why nissan ECU would need it? - O2 & TPS give all necessary info)

 

02 and TPS won't give the ecu information about exactly how much air is been ingested. ie.. the MASS of the air. 02 is just a/f and tps is just the throttle position.

In reality, the only electrical that the engine needs is for spark. But as engine control gets more advanced, more parameters are needed to used for calculations.

Engine with just a carburator and engine engine with an advanced obdII electronics will both run well. But the one with the obdII, will run 10x cleaner, start easier, most likely have more hp per liter and get much better gas mileage. Not to mention last alot longer.

 

Yes, that is so. But THE crappy VG intake roulette hogs all hidden V6 pwr possibilities...