Last week i installed my stillen y pipe. WOW.. This is my favorite mod I've done so far, soo much more power and sounds great also. After i installed it, i noticed that i got better gas mileage. I usually get 75 miles to a quarter tank, after the y-pipe i hit 100 miles to the quarter tank with my normal city/freeway driving. Has this occured to anyone else one that installed the y pipe? Maybe my Cat was clogged?

 

dude you been on since 12/02 and finally installed a y-pipe? GEEZ get with the program! lol jk, yes i must agree this is also my favorite mod also.

 

Im glad it worked out really well and you like it brian, Hey did that check engine light come on at all???

 

no, it didn't come on. But SURE SAVES GAS!

 

will you pass smog with a y-pipe in CA?

 

not the visual part of the test

 

eh brian did u put ont he front tube? if u plan to, get a o2 simulator..

 

Do you have any pictures? I'm in the middle of looking for parts to replace my front exhaust tube assembly because the flex is leaking. Where did you get the parts? Part numbers? What about emissions tests? Would it still pass?

 

just buy it from stillen or cattman. Depends if you car maxima is a cali or fed spec. You will pass emission from past experience with friends and brother's car.

 

This might seem a little off topic...but I bought a wsp y-pipe off ebay, the guy told me it was a fed spec, but its cali....anyone know where I can get a piece to connect my y to the manifold? Thanks

 

Thanks for your response. My car is a 2K CA-Spec Maxima. I won't need to get the emissions done until 2007, so I'll try out the after market pipe and worry about the emissions a few years from now. Thanks again...

 

Does anyone else have any specific gas mileage increase #'s?

I'm in CA and hate to have an especially attentive smog technician notice the Y-Pipe, so I've never done the mod, because I hate to redo my system every other year. I like to put something in and forget about it.

On another note. Personally I think the smog equipment is a load of crap. Sure, we produce less emissions because of all the junk we add to our vehicles, but is it worth it? We get less mileage and use more fuel to get 'lower emissions'. I have to wonder how much more fuel we use and if *overall* emissions are higher (or the same) with the addition of the smog equipment.

Lastly, how difficult is it to get to the old precats to replace w/the Y-Pipe? When I had my P-0420 code, I gave it to a friend for $100 to change out for me b/c I really didn't have the time (or the right tools), to change it out.

 

I've noticed a minor increase in mileage with the combination of intake and y-pipe.

 

Yea its supposed too less restrictive,
No precats...like oem

 

I'm with you... it maybe a good idea to stick with the stock items... After reading the threads about the PO420 fault codes and how many problems are being created when adding the Y-pipe. I don't know about you, but I would not be able to just ignore a SES lamp and hope that the smog tech doesn't catch the change... My car already gets excellect gas milage. I would not change the pipe just for that reason.

 

i used to get ~330 per tank which worked out to 22-24 all around. Worst ever recorded was 21.4mpg. Now i get ~430, which usually ends up at 25-26mpg. The best ever recorded, 28.6mpg, about 70% highway that tank. the last two weeks my 02 has been shot, so i'm getting like 24-25 last couple tanks with the SES light on.

 

I just passed emissions with Stillen Y-pipe yesterday for the third year straight. And it included a visual check.

 

they're supposed to fail you on the visual but....it's really up to their discretion.

 

if it does increase gas mileage thats str8 i jus got my wsp y-pipe yesterday and im installing tommorow, Can't Wait

 

I've actually decreased in miles per gallon with my wsp y pipe , cai, cat-back ,and test pipe......O' yeah cant keep my foot of the pedal neither!!!!!Maybe that's the problem?

 

yes that is your problem.

In theory, if you add bolt ons and be steady on the pedal, you will gain MPG, because you won't have to step on the gas as hard because of the powered you have gained. Thats just in theory though.

 

it is true though, with bolt ons u'll gain mpg as long as you don't add more fuel into your a/f ratio.. and u'll gain even more when you lean out the a/f curve.

 

There's a visual test?! LOL wow I passed my tests with flyin colors. I didn't notice an increase in gas mileage, if anything since I am using more power I noticed a decrease..

 

"I'm in CA and hate to have an especially attentive smog technician notice the Y-Pipe, so I've never done the mod, because I hate to redo my system every other year. I like to put something in and forget about it."

These people make 7or 8 dollars an hour. If they get bent out of shape about it then slip them a 10 or a 20 to keep it on the downlow and pass you. I garuantee you they will take it.