I just put the y-pipe in and I am curious. Does anybody else have the buzzing problem? When the engine is between 4-6,500 occasionaly it sounds like the exhaust is buzzing. I'm not sure if an exhaust gasket is bad, or it is the flex pipe? Could be the heat shielding? Not sure! If anybody else has noticed this i'd like to know.

Best performance piece for the money. Stillen is running a deal $349 for the pipe. Call andrew at stillen for more details. I also just bought a whole OEM brake replacement. All 4 rotors and pads for under $600. The rotors are cross-drilled and chamfered. They work awesome on the car and they are a direct replacement for the stockers. I guess they look kewl too!

cya
Ryan

 

What does your Y pipe look like. Do you have 2 pieces. I had one of the first ones they made and it made a noise that sounded like a water sprinkler. They redesigned it an after installing it I no longer have the problem.

 

It is a two piece. Is that the older or newer version. I hope it is the newer version, cause stillen told me I had to wait for the pipe because they were still making them.

 

I got the Y-pipe too and it has two parts but I been too lazy to put it on, I was wondering how easy was it for you to put it on.

 

Please view these pictures...
http://www.geocities.com/y2kevse/images/brakes1

I have posted about 4th gen oem rotors vs. 5th gen oem rotors before. Please make sure you have the 5th gen oem rotor thickness.

 

the stillen Y comes with 2 separate pieces, but we don't use both of them. we have no use for that short front pipe.

 

Hey man i was just about to buy a Y-pipe from Stillen and was just wondering if it really helps out on performance? and how easy is it to put on?
One more things (maybe you can help me out with this)
is it worth it to pay 549 for stillen muffler?
Thanks
Ricky
Hiexp@hotmail.com

 

No it's not worth it to by a stillen muffler, because someone else manufactures it. You can get the same muffler, if not better from Greddy, HKS, Magnaflow, or many others. I also would like to know what the performance is on the Y-pipe.

Thanks

Tom 2kGXE

 

The y-pipe has definitely shown an improvement in performance for me. Being in detroit, there are quite a few mustangs running around. I was dead nuts even from a 1'st gear roll with a 99-00 mustang GT stick. It is fairly easy to put on, but then again I am a mechanic. I was curious about the other reply that said they have no use for the second piece of the pipe. Do you just not hook it up? Seems odd. Please explain!

 

of what I was about to get into with this y-pipe and it seems that I would have to use the second peice of the stille Y-pipe to hook it hup to my car. Is this because I do not have the Cali-spec car?

 

The second piece is for federal emissions vehicles only. So, it will not be used on CA spec'ed 2000 body styles. Also, it can not be used on any 2001 Maximas since they are all CA emissions now. This is the reason I bought a 2000 front-side exhaust manifold... so I can use this second piece. All you have to do to use it is relocate your two O2 sensors after the pre-cats to after your main cat and install both pieces of the y-pipe along with a 1995-2000 federal spec'ed front side exhaust manifold and you have essentially removed all of the negative points about having a CA emissions equipped car. As soon as I have the bucks for a y-pipe I will complete this mod and let everyone know.

 

So the relocating of the 02 sensor is for cali-spec cars wanting to use the second pipe. In my case would that be required?

 

errrrrrrrrrrrrrrrrrr. buzzer sound. The y-pipe comes in two pieces. They both go together wether or not you have any different type of car. The whole assembly comes as one from the factory. There is an extra o2 sensor hole in the y-pipe that comes with a plug if you do not have the 3 o2 sensors in the 2001. What are all of you talking about? Did any of you actually put the y-pipe in, or are you going off of what other people say?

 

i put mine in with Maxedbandit..there is a hole for the O2 sensor and all 5th gen and 99 4th gens have 02 sensors for that hole...98 and down...they use the the plug provided by stillen in place of the 02 sensor...at least in cali that is...

 

Caveat emptor! There is a strong likeliehood that the modification proposed by Desert Pearl will generate a check engine light unless the CA/NLEV-spec ECU is replaced with a Fed-spec ECU.

My hat's off to Desert Pearl for being willing to try this experiment. But I would urge everyone else reading this post to wait until Desert Pearl completes this modification and reports his results before trying it themselves.

 

Foglight... I believe you should be getting the buzzer sound, unless I have been fed incorrect information from Stillen. Does anyone have a picture of the two piece y-pipe from Stillen??? This would solve our debate immediately.

I was told that the 2 piece y-pipe consisted of one piece like Y2KevSE has on his car http://wwwcsif.cs.ucdavis.edu/~chin/...es/y_pipe.html and another piece that curves up from the right hand side of this pic up to the front exhaust manifold. If this is the case, my earlier statement is correct and the CA emissions cars would only use one piece, not both! The second piece would only replace the front precat and won't even bolt up to the CA emissions front exhaust manifold.

Someone settle this and find a pic of the Stillen 2-piece y-pipe!!!!!!

Also, Y2KSE is correct. I don't believe the reloaction of the O2 sensors will cause a check engine light, but I will be the guinnea pig and find out.

 

cali max's use one pipe and federal max's use both pipes. right?

 

[QUOTE]Originally posted by Foglght
[B]I just put the y-pipe in and I am curious. Does anybody else have the buzzing problem? When the engine is between 4-6,500 occasionaly it sounds like the exhaust is buzzing. I'm not sure if an exhaust gasket is bad, or it is the flex pipe? Could be the heat shielding? Not sure! If anybody else has noticed this i'd like to know.

Hey Foglght, the buzzing sound of your Stillen Y-Pipe has been known as bee's in a can, so no it's not heat shielding or gasket. Cattman Y-Pipe is not supposes to make that buzzing noize. Y-Pipe is known to add around 20 HP, but for best result use with PRCAI or OSCAI, that may give something between 20-28hp and if your exhaust is tweak then maybe another approx. 8-10 hp gain, not bad at all.


Cheers

Double A

 

Question? so a Y-pipe form stillen is worth the money right?
i am thinking of buying one but dont know how it works and the HP gains. can some one help me out?

 

I believe so, based on what I have been told from Stillen. To make sure, I was asking for pictures of the Stillen 2-piece y-pipe.

 

I have pictures how do you post them!

 

never mind

 

more of the Y not unwraped just in case I have to send back!

 

Again!

 

last one!

 

THANKS Max_Vader_SE. This is exactly what we needed.

So, the 2nd piece of the Stillen pipe does work exactly like they told me. This short piece will ONLY be used on the 2000 Maxima with Federal emissions. It won't be used on any other 5th gen Max, because all others have CA emissions and will have a pre-cat where this pipe should go. Since this precat is integrated into the exhaust manifold, this pipe won't even bolt up to the CA emissions manifold (ie it's used on 2000 Federal cars ONLY).

This is where I got the idea of changing the front-side exhaust manifold to a 2000 federal emissions one and actually using the second piece of the Stillen y-pipe. If I can fool the ecu (which as Y2KSE has pointed out, hasn't been proven yet...), then I can get rid of BOTH precats instead of only one.

Monday I will try to get two O2 sensor bungs welded onto my cat-back. I have already prepared a piece of copper tubing that is bent to follow the subframe and brake lines back to my cat-back (See pic below). Hopefully I can get everything hooked up by Tuesday night at the latest. I'll post results later next week.

 

More info on this O2 sensor plug....

The idea behind this extra O2 sensor bung is so that you won't generate any check engine lights. There are two cases for our car... 1. Federal Emissions and 2. CA Emissions.

Case 1 - Federal emissions. With this setup there is only 3 O2 sensors. One on each side of the y-pipe by the exhaust manifolds and the third is located after the main cat. In this case, all O2 sensors remain in their original location when you install the y-pipe. The extra bung on the stillen pipe is plugged. By installing the y-pipe you haven't changed what or how the O2 sensors are reading.

Case 2 - CA emissions. With this setup, there are four O2 sensors. The first two are the same as on the federal car (except the frontside one is bolted into the exhaust manifold). The rear two are after the precats in the stock y-pipe. None are located after the main cat! Now, with the Stillen two-piece pipe, as I mentioned in the last post, these CA emissions cars only use the first piece of this y-pipe. By doing this, the front precat remains in the exhaust system. The purpose of the extra bung is to move the O2 sensor that would was after the backside precat to after the frontside precat. This way, both downstream O2 sensors are still located after a precat, it's just that now they are both located after the front precat, not one after the front and one after the rear as before. So essentially we are fooling the ecu to think that all of the emissions equipment is still intact.

Once again, I am just taking this idea one step further (hopefully with no check engine lights). I am relocating the downstream O2 sensors to after the MAIN cat instead of the front precat. The front precat I am also removing by using a federal emissions front-side exhaust manifold and also by using the second piece supplied with the Stillen y-pipe. The idea is fundamentally sound since the only difference between the main cat and the precats is that the main cat has a high surface area honeycomb which is more efficient at removing carbon monoxide, hydrocarbons, etc. The precats are a low mass honeycomb which is located closer to the engine, designed to heat up quicker providing temporary "cleaning" of the air until the main cat can warm up to normal operating temperature.

Anyhow, enough with the boring techno talk. I'll post again next week with check engine light / O2 sensor relocation information.

 

Thank you Desert Peral your a life saver.

 

After reading this thread, I have an observation. This is in the case of the Cali spec emissions. If we move the front O2 sensors to behind the main cat and eliminate the pre-cats as Desert Pearl is proposing, then the only time a 'check-engine' light would possibly occur is when the engine is cold. By not having any precats, you would have to wait for the main cat to warm up before emissions would be 'clean' again as measured by the sensors. Anyhow, it seems like a good idea, and if it works, that would be great

 

Would removing the heat sheilds make the removing the old "Y" any easier? Also would I have to put the heat shilds on the new one?

 

This is true. In fact, the likelihood of this generating a check engine light is even less, because there is already some delay before the O2 sensors heat up to operating temperature also. Before an O2 sensor heats up, it outputs a constant voltage that the ecu recognizes as an invalid reading, so it continues to run in open loop mode (ie ignoring the O2 sensor). Once it heats up the voltage should fluctuate around this nominal voltage. The ecu will see this and go into closed loop mode and actually adjust the car based on it's readings. Hopefully our CA cars will heat up the rear cat before a check engine light is generated.

(disclaimer: I am assuming in this statement that the downstream O2 sensors work like the ones closest to the engine which are used to tell the ecu if the car is running rich or lean. I believe this to be the case, but I'm no expert.)

 

I can not get the old one off, I tried really really hard and elbow grease is not the word. Any suggestions on getting the old one off mainly rust problem.

 

Did you soak it with WD40?

 

Yes that help to loosen 4 of them but the front 3 and 1 on the Main cat will not move and I don't want to break the screw.

 

Have you tried breaking them loose when the car is still hot? I'm not sure if this will help, but it's worth a try. Be sure to use some anti-sieze on the bolts when you install the y-pipe, or you'll run into this problem again.

 

When I first tried to get tem off the were warm and they did not do nothing then I sprayed them with WD40 and got this funky smell and let that soak awhile and about 30 min later sprayed a little more and only 4 of the 8 came a loose and I did not have the BIG Wrench for the O2 sensors it requiers a 20mm and I only had 19mm (that sucks) now I don't know what to do.

 

1. I have the cattman Y. Even it buzzes some at high rpms. No big deal though.

2. You will not get 20hp from the y-pipe. We've dyno'd 2 2000 fed spec 5spds and the ypipe combined with the SI (on one) and the PR CAI (on the other) both produced an extra 13 hp to the wheels. You will not get 20 hp - 25 hp as I believe Stillen suggests. That's not even correct at the crank. If you assume 15% loss with a 5spd you are still only looking at 15-16 hp at the crank combined.

That 13 hp makes a big difference though and is definitely worth the $$.

If you do a search you should find detailed threads by madmax2k and myself with dyno charts.

 

Has any of you ever been caught or question about you Y-pipe? Also can any sugest how I can get my old one off, remove heat shields, etc....

 

How do you remove the O2 sensors?