That **** with numbers is scary, man.

:werd:

It's 2.5" O.D. but with thin wall pipe I.D. and O.D. are pretty close

you close but not quite.


OEM Y-pipe exit spec is as follow ; avg 2.5'' OD and 2.350'' ID ,, its a double wall exit (inner sleeve)

In for laughs!!!

there shouldn't be any laugh.... please he is doing a nice personal project and there hasn't been any aftermarket part being sold as a 3.5'' anyway , on the 350z or 370z , unless you prove me wrong with a link somewhere ;)

In general 3'' is still good. :tup: (IMO there is a but...)

:iagree:

Correct. It's a cool project. I'm just trying to get him to correct the major issue before he gets to the end and regrets not doing it in the beginning.

Hi ! I'm wall ... Talk to me :D

You've been lead to water. It's on you to drink. :rofl2:

Sorry Chuck, but I think you are the wall in this discussion ...
Everything as been said, every aftermarket are 3in ...
Mandrell bends, Y pipe and HFC will provide the necessary
flow to have gains.

I respect your opinion, so from now, wait for results and then,
we'll talk again !

mostly due to clearance..

:rofl2:

Not even close. What aftermarket exhausts are 3"? The ONE that's on the market? The one that has gains simply because it removes the 2.3" bottleneck in the stock Y?

Here, I did the math for you. The area of a single 3" pipe is 45.606 cm^2. The area of two 2.5" pipes is 63.342 cm^2. That's a huge difference (17.736cm^2). You're introducing a bottleneck at the y. For comparison, a single 3.5" pipe has an area of 62.071 cm^2. Go back and read Megan's posts. You must have missed the part where he build a single exhaust. You should be taking his word for it because he's already done all of the testing.

All I have to say which is already a big hint is if we aren't talking about headers, the next spot to look at is how the y-Pipe is made and even more importantly is the throat aera which will play one of the biggest role.

that's not only coming from me but by Find Custom Exhaust, Header Collectors, Race Mufflers & More | Burns Stainless

The Y collector will be assemble soon, i'll write the theory
behind my build ... But yes, it's a critical part.

My caliper said I.D. was 2.4"ish

how about those then.
they are in lock mode at 2 different axis .

edit; we don't have the same y-pipe. do we?

http://www.the370z.com/members/megan...214-172811.jpg

http://www.the370z.com/members/megan...214-172737.jpg

I can't tell from your picture but if that's the factory y-pipe, then they are identical between G and Z. The battery was dead on my caliper so I had to guesstimate the reading. Not to mention I had the factory gaskets bolted on the flange so they were kind of in the way.

I'll agree with 2.35 I.D.

I should have bought a caliper with a damn dial instead of digital readout

no worries,,, I'm just quite strict on measurement ;)
I kind of jumped when you replied it was 2.4 instead of 2.35''
hehe

sounds like every engine rebuilder i know :P

The design
 

Ok ! Spring is alomst here in Canada and it smells like my Z with be at the shop to build the new exhaust soon. Every pieces as been hand polished ( pics later ) and they are looking great !

I have a question about my design ... I want to make the tube longer to have a deeper sound and I tought of making a "detour" before reaching the muffler.

Here's a beautiful drawing to illustrate my plan :rofl2:



Attachment 85409


What do you guys think ?

Awesome

Sent with TapAhoe

I'm no expert but I had to take some fluid dynamics 25years ago in school, water in pipes, but air should not be that different. If my memory serves me bends will create resistance to flow and equal many feet of extra straight pipe. Why add restrictions to an exhaust, will this not be counter productive to performance?

Is the purpose of the build only for style and to make a specific sound, or are you hoping for performance gains?

That bend is bad news for flow.

My goal is performance but I want a deep sound as well

But I didnt mentioned that I'm gonna build an "optional" pipe for track
purpose only that will bypass the 2 resonators and that bend.

It will be detachable with v-bands ... So 10min before track day, i'll
switch to this straight pipe, thats the goal tho ....

So what's the purpose of the bend?

Sent with TapAhoe

Longer tube = deeper sound

My opinion is you should play with different size of resonator and muffler for the deep sound instead of having unnecessary long exhaust tubing. ;)

Yeah, extra length with some hard bends is a much worse solution than adding one or more additional resonators.

Begining
 

So it as begun.

At last the weather is more clever now here in Canada, so the Z is out since yesterday. At the shop, everything went well to remove the Nismo exhaust. This part is out and will be clean soon for sale.

I red alot about those devil cats bolts but never tought it was going to be THAT pain in the a** to remove. None of the cats are out yet, almost one but it still attached bye the faith of that devil bolt that I did cut. I tried to undo it the way it should, but I stripped it.

On the driver side, I have a problem. I don't have a direct acces like in the videos to unscrew it. A part of my steering assembly is blocking the way, so I can't even try to unscrew it ! Is that something special on the Nismo model ?


Anyways, can't wait to begin the fabrication of the new setup !

I'll keep this tread updated with pics in a few !

If you haven't already purchased an HKS muffler and all that...

Look at an Aero Turbine muffler... proven to flow better than a straight pipe while muffling sound.

Have one on my DD, sounds great.

Cats ...
 

Cats are out !!! Holly victory ...

Now time to fab !

Here is the genious welding that my friend does, this one is the conversion of those Berk HFC to V-band flange:


Attachment 86760

All were already purchased :/ but thx for the suggestion !

Those are some nice welds

Thx man !

Progress
 

It was a great night at the shop, the hardest part is done, The "Y" merge pipe.
I have to say, without flex pipes, its pretty hard to fit right !

Here's a pic:

Attachment 86908

So it's done !
 

At last, the exhaust as been fab. My friend and me finished it last week and i'm really happy of how it turned out. Fitment is mint, and it sounds awesome.

Here is some pics of this journey:

It all begun with polishing...
Attachment 87278

Than some grinding...
Attachment 87279

More cutting...
Attachment 87280

Some great welding
Attachment 87281

Than we saw some pieces coming together:

HFC converted to V-band and Y merge pipe
Attachment 87282

Attachment 87283

Modified resonators:

Attachment 87285

Attachment 87284

I had to cut a bit of the rear bumper ...

Attachment 87294

Here is the result, see the tight fit everywhere !

Attachment 87286

Attachment 87287

Attachment 87288

Attachment 87289

Attachment 87290

Attachment 87291

Attachment 87292

Attachment 87293

Yes ! Its croooooooooked :rofl2::eek::happydance:


Here's the sound clip, more to come !

https://www.youtube.com/watch?v=OYCl-6b0vOc


That's it ! I hope you enjoy the post ! :driving:

Why some pics wont come up ??? :(

for a second I thought it was my Y-Pipe ! hehe


Nice job on finishing up this Project ! :tup: