It is hard for me to believe that Nissan would do this if it hurt performance badly, but then again it is hard for me to believe that it wouldn't...

I'm talking about the exhaust pipe right in front of the mufflers. Now, these are supposedly high flow mufflers, and dual ones to boot, but the pipe in front of them, at least on my car, was crimped/crushed in half!

So, the volume of gas going through that thing is about half (I know...some venturi effect goes go...blah blah) of what it could be, and I would think that volume is less than it should be!

Has anyone else here noticed their Maxima's pipe being this bad?

I would think that a great, not too expensive, upgrade would be to get this section replaced if it can be shown that the volume of gas exceeds the capability of this crimped section.

 

are you talking about this one?

 

That's the one...maybe all our Maximas are that way.

 

they are definately that way i had mine removed when i installed my greddy's and i noticed that as well.

 

Go with aftermarket pipes, Greddys or Magnaflows. No more problem Let your MAX BREATHE...

 

Yep, thats a typical stock pipe choking your Max...

 

yup, that's the stock piping. that's why i went with custom 2.5" catback. no regrets

 

not sure about venturi effect, but i am familiar with bernoulli's principle. but would that apply. doesnt even matter.

 

Thats nothing. Someone should post up a shot of what the collector pipe (b-pipe?) going into the cat (looks like). Talk about kinks...shessh. It's unreal. That mid-pipe kink is nuuutin compared to it.

 

Don't you guys find it odd that Nissan would join the 2 downpipes together into one pipe only to split it up again in the rear? It's probably the only way Nissan can do the exhaust due to the transverse engine = unequal pipe lengths but I found that odd.

I bet it wouldn't be THAT bad to have true duals with a traditional X or H pipe inbetween.

 

I didn't look that far up. Could it really be worse?

What it looks like is needed is some different pipes then. The two high flow mufflers there shouldn't be restrictive at all. It's just the piping getting to them that's the problem.

Being as cheap as I am, I don't know if I'll go for an aftermarket setup like the one from Cattman or not (although I think it is probably worth the money). Instead, I may just visit my local shop to see how much they would ream...I mean charge me for getting rid of the problem areas.

What would be good, if someone like Cattman or Greddy, or whomever would sell their kits in modular format...with or without the mufflers. That way, those of us who like the stock sound can get the benefits of the better flowing exhaust without the added expense of the mufflers (these would be at least $300 of the total I would imagine).

 

If I was to put on an aftermarket pipe would Nissan void my warranty?

 

I agree, and with the B-pipe out of the way their is all kinds of room to run a true dual down the center...



Things that make you go HHHMMMMMMMM...........

 

In reality, the only thing I think they could complain about for that would be the exahaust/emissions warranty stuff.

 

Restricted pipes produce 265hp. Hmmm.......

 

1. fluid dynamics are complicated (air is a fluid). millions of dollars worth of exhaust are sold evey year to gullible people that think just putting bigger or louder exhuast on a vehicle will make the seas part and the birds sing.

2. bigger is not always better.

3. this 265 hp version of the engine is considered a step up from the 250 hp altima, etc. It is also competing with the 280 hp avalon, among others. If it was really possible to increase peak power just by NOT FLATTENING THIS PIPE, even if low rpm power was sacrificed, don't you think Nissan would do it?

4. I'd love to see some dyno charts. Unfortunately, most of us don't have access to a dyno, and the few charts you do see are from someone with an agenda, such as the mfg of the exhaust system.

(sorry for such a rant on my first post)

 

Well consider the Nissan designed Y pipes for the 3-4-5 gen maximas. compromise at best. Adding a performance version = 10-15 hp right there. Nissan made the pipe to FIT/CLEAR. Not necessarily for the best performance.

 

Welcome, rant away!

Flattened, kinked, squeezed from stock y-pipe on, plus vacuumed intake snorkel controls amount of air in/out of cylinders at high rpm. It might have a lot to do with product placement. Possible marketing on Nissan's part not to give 04-05 Maxima better performance numbers than 03-04 G35 (+5 hp on the larger Max against TL, blah blah blah)? This is merely a speculation on my part though.

 

RH-good point regarding the G35.

Jeff, I hear you on clearance issues, but that just seems too easy. Nissan has a pretty big budget compared to aftermarket exhaust companies, if it was as easy as "make a pipe just like the stock one only bigger" or "make a pipe just like the stock one only without the flat spot", one would think Nissan would do it, especially considering how many years they have spent developing this car.

 

repost annoy me, especially when the original thread had more info. so carry on in:
http://forums.maxima.org/showthread.php?t=416974