I was looking at Custom Enterprise's y-pipe and high flow cat. I was wondering a few things.
-Are they street legal? I think I was told you can't replace your cat unless yours broke. Also, doesnt the y-pipe eliminate some of the sensors, therefore making your exhaust configuration unauthorized and illegal?
-Does anybody have this y-pipe and cat on their car? If so, did you notice a decent power gain as clained on the site (24hp 23tq on a stock 1997)?
-If I put these on my Max and left the stock headers and rear section, do you think it would be really loud? I do not want a loud attention-getting exhaust.

 

I have been asking these questions for awhile. It's won't be much louder than stock that was my main concern. It will elimate both pre cats which yes is illegal, and the gains should be 18-20hp. I would say go for it. I am going to do it and my state has an emission inspection we have to go through each year. Check out warpspeed though (type warpspeed in ebay) I have researched this and think this would be the best one for the 2000 max.

 

as long as your car is warmed up before the test you are fine....just tell the guy that i dont think he will mid letting it run for a few mintues...mine dosent at least when i go for emmissions (my 97gxe-->2001Se)

 

OK, so is it legal to swap out my cat even though I think it is operating normally?

 

if you replace it with another cat then no, and i have a warpspeed on my 2k se and i like it a lot. performance is very nice and the sound is good too, i would recomend doin the rest of the exhaust to compliment the ypipe though

 

What do you mean when you say its illegal to replace it with another cat?

 

A aftermarket cat is made to be as free flowing as possible, therefore nissan designed a cat to keep emissions down, thus why we have pre-cats in are stock y pipe, when you remove the cat for a aftermarket cat there is so much free flowing gas especially with the 2 pre cats removed in the y pipe thats why you get such a nice gain from the y pipe because it is so restrictive..keep your stock cat and go everything else aftermarket if you want, you wont have troubles becuase your cat is the last step to restrict the smog and other elements present in the exhuast gas (Emissions) you will be fine if you leave the stock cat, and have a y pipe and aftermarket exhaust system IMO...

 

It's illegal to replace any working cat only if the car has under 50k miles. It may be more, as recent posts have stated 80k. And it's not going to make that much of a difference with jsut cat. If you keep everything else stock, you will barely notice the sound difference, and the people next to you won't notice at all eitehr, so it's not attention getting at all. 23hp/24tq gains, seems high.

 

OK, I have 82,000 miles, so I'm OK. the 23/24 gain is a 1997 Maxima with the ypipe and cat versus a stock 1997. I know the cat isnt going to give me anything close to 24.

 

Either way, only I/Y/E will probably give you that, not just either or, it's called marketing.

 

As I said above, I understand that the cat alone will not do anything close to 24.

 

Neither will the cat + y-pipe maybe in rare occasions but not typical, as I sated above as well.