Excluding for the moment those states that have restrictive exhaust laws like California, what are the physical differences between a Y-pipe that is street-legal and one that is not?

 

aftermarket y-pipe doesnt have CAT like the stock y-pipe

 

street legal. removing the cat and replacing it with a straight pipe is illegal

 

Y pipes are for track use only.

 

The Budget y-pipe takes out two pre-cats used for cold start up emissions, to my knowledge.

 

Any piece of equipment that disables or removes emissions equipment is illegal for street use.

 

That is what I suspected (re: the cat being the essential element).

From what I've read here, y-pipes lack the pre-cats of a stock pipe, but will fulfill emission requirements when the engine reaches operating temperatures (assuming, of course, that everything else is in place like the cat, front and rear O2 sensors, and the muffler).

 

Technically the y-pipe is illegal because as THT said, BUT since the y-pipe only removes the precats, which filters your exhaust only when the engine is cold, your normal CAT will still be in place. And since your car needs to be warmed up to normal operating temp in order to take an emissions test, your car will pass if you have the y-pipe. So yea its kinda illegal and legal at the same time.

 

What kind of hp gain would you expect?

 

Depends on which generation Maxima you have.

No emissions equipement is removed on a 3rd generation VG or VE. Only 4th+ Generation Maxima's have pre-cat/s removed.

 

For what year car are ya asking?

 

How about 15 to 25 as a ballpark?

 

10-17hp is a more realistic figure

 

I doubt you can get more than 12-13whp out of a ypipe. People often says 20+hp because you WILL feel it, but that is mostly because we "underestimate" HP. A clean, honest to godness 10 HP at the front wheels will certainly be felt... people often think 10hp is insignificant.

 

Why not ask people who dyno-ed their cars?

 

Or check in the dyno forum ...


Might help ..

 

With a 4gen 5sd you can expect ~18-23 hp at the wheels. With a y-pipe and an intake. My car stock made ~161hp & 174tq at the wheels. With a catman SS y-pipe {the one with the slip joints} and a Place Racing CAI it went to 184hp and 196 TQ. I believe the intake add ~6hp to the wheels. I have a 99 SE. My car was tested on a dynojet.

 

When I got my car inspected, they didn't even pipe test the car...they just checked the computer to see if I was throwing any emissions codes.

 

Yeah, some states only do an OBDII scan on 96+ cars. IL is one of them...lucky me!

 

u can always make friends with a shop owner or 2 and have them give u a slip saying that you passed. cops won't check

 

They eliminated inspections in Florida five years ago. Consequently, I see a lot of vehicles running around here with straight exhaust pipes. We also are supposed to have a law against excessive noise...but it is never enforced!

So, it is not like I have to worry about running a track setup on the street. I am, however, concerned about the environment.

 

If you're concerned about the environment, and want to keep emmissions down to a minimal, leave the stock y-pipe.

 

I understand that the sole purpose of the precats is to reduce cold-start, O2 emmissions until the main cat warms up. On my car, it takes about 30-45 second until I reach operating temperature. So my question is this: how much more O2 would I be releasing into the atmosphere during those 30-45 seconds?

Speaking of aftermarket pipes, I noticed that you have one on your car, so essentially what you are telling me is, "Do as I say and not as I do."

I plan on keeping the rest of my exhaust stock, and that is what I meant by what I said above. I'm balancing my environmental concerns with my need for speed like everyone else here.

 

I never posted anything about my concern of y-pipes with relation to the environment, so I'm not a hippocrate if that's what you're implying. .. I don't care what you do.. You're the one that stated your concern for the environment so I was giving the answer that would best fit YOU. I have y-pipes on both my cars, and a test pipe on one of them if that's any help.

And your original title is asking street or track use, and now you're concerned how much more emmissions you'll be giving up during warm up? Well taht answer I do not know, all I know is if you're concerend that much with the environment, then a y-pipe isn't for you because as stated earlier it eliminated pre-cats, pre cats help reduce emmisions in the warm up period, and I'm not sure how valid your statement of your car reaching operating temperature in under a minute. But I gave you my advice.

 

excuse me, but if im not mistaken, "operating temperature" isn't reached until about ex; 5 minutes of urban city driving.

 

Obviously he's refering to the catalytic warming up to it's operating temp.

 

So you agree with him then? 30 seconds?

 

I'm almost sure it takes more than 30 seconds for the main cat to warm up, maybe closer to 1 minute or 2, but obviously no engine is gonna warm up completely in under 5 minutes.

 

are you sure hes using the right term then? "operating temperature"? sounds more like warmed up cat to me then. certainly not operating temp.

 

dj-rp Get a y-pipe ....

 

Got one...and look at all the trouble it caused me when I told others about it.

 

which one, pics please?

 

I just bought a Y pipe, Imported it, and It wont fit, Wrong flange pattern and height, i was told it would fit..

Apparently its for a 95-01 maxima or i30, anyone wanna buy it :P