What is the best y-pipe/b-pipe combo for power that keeps the car sounding stock. I mean, I want to be able to be driving at low RPMS / partial throttle and have the average joe not notice the exhaust sound difference from a stock maxima unless I pointed it out to him. Is that possible?

Also, I've heard that sometimes they make clunking noises? What's up with that? How do I avoid that? If its going to turn my maxima into a rattle-trap I'd rather not.

I might want to do something with the muffler is I can get a very quiet one with justifiable gains.

Lastly, what kind of power gains would I see with the y&b-pipe, plus cold air intake combined, if I'm otherwise stock? Would it help gas-milage at all?

Thanks!
-Kyle

 

The best NA setup that provides the most amount of power with the least amount of noise is intake, Y-pipe, RT cat, and stock exhaust. If you add an aftermarket exhaust to this, it will be considerably louder. The above setup is as quiet as stock at lower RPMs. If you install the stuff correctly, it won't rattle.

 

Got that same setup with no clunking. Actually the CAI intake makes more noise than all the pipes running behind it. Just replace everything but the muffler and you'll be happy and faster!

Power gains = CAI 6-13, y-pipe 12-20?, RT CAT 7, b-pipe 2-3
Total 27hp+

 

A lot of the boominess in sound from an aftermarket exhaust comes from the shape of the sound chamber on the muffler section. The reason why so many aftermarket exhaust systems like Stillen, Greddy, and HKS sound so boomy is because they all have the same general shape in the sound chamber.

I had a local high performance exhaust shop fabricate a muffler section for me that had a 2.5 inch inlet diameter and a 2 inch muffler outlet -- It was just a generic brand high flow muffler but the sound chamber is noticeably longer than the old Stillen muffler I had -- but the shape of it also seems a little shorter from top to bottom but a little wider left to right if I recall correctly --

A decent flowing exhaust muffler section doesn't have to be obnoxious sounding. But all those aftermarket companies know that most of their buyers are younger folks who want to imitate the sounds of big V8 engines. So they design them to have a strong low frequency booming sound.

 

If you want quiet you dont want a cat-back. I had the CAI, Stillen Y and RT cat and it was only loud under WOT. Now with the 3" cat-back it is loud! I got a warning for being too loud. The CAI is still louder than the back of my exhaust(unless you are behind me) under WOT. There is not a way to have a quiet cat-back.

Kirk

P.S. Too loud for exhaust means that they estimated it at 110 db, legal limit is 93db.

 

Try sticking with the stock muffler. It is the quietest one out there. The HKS is still quiet, but it still drones. I have the Cattman Y-Pipe and the CAI, if I were to add a different muffler, it would probably be significantly louder. But this is an assumption. As I have heard, sticking with the stock muffler is the way to go, but change out the y-pipe, cat, and b-pipe. You will only gain 1-2 horsepower (maybe) by changing the muffler. But if I am wrong on any of this, someone please correct me.

 

How about adding the Y2K+ muffler to the b-pipe. Wouldn't this keep it nice and quiet but give a few extra horses because of the sequential flow design?

 

A few weeks ago some people reported having done this with pretty good results (slightly more power w/no more noise). I had thought that that newer muffler had some sort of complicated electromechanical component that controlled when the muffler flap opened, but the recent postings imply that the muffler is more or less a bolt-on replacement.