Upgrading the Exhaust of the N54 Z4

[Armando1969]

I wanted to upgrade the Exhaust on my z4 3.5i because of two reasons:
1 As Preparation for a performance upgrade.
2 Some more sound without it being obnoxious.

So what did we do.
Take out the center section of the Exhaust and inserted a Fox X-pipe. This way you get a true X-pipe and get ride of the restriction in the piping to the right backbox. And while we had the Exhaust of the car we installed some stainless/Carbon endpipes.

 

[Armando1969]

The parts before we put them on the car.

 

[Armando1969]

This is the standard exhaust with a blow-up of the restriction that we got rid of

 

[Armando1969]

The work in progress

 

[Armando1969]

The end result.☺

I think it looks nice and it still sounds very civilised, you only hear a difference when you go full throttle.

In two weeks the next stage: Downpipes with racecats and silicone inlets.

Gr Armando

 

[pbondar]

What state of tune are you running?

 

[Armando1969]

What state of tune are you running?

At this moment MHD Stage 1+, after I get the downpipes I will switch to 2+.

 

[Torgus]

Is there a reason you want cats in your downpipes?

Exhaust looks sweet!

 

[Armando1969]

Is there a reason you want cats in your downpipes?

Exhaust looks sweet!, thanks.

Yes, need it to stay legal for our Dutch yearly inspection, going back and forth between cat and downpipes every year is too cumbersome for me. Plus my end target is around 450 horsepower at the engine and I can make that easily with cats.

 

[Torgus]

Yes, need it to stay legal for our Dutch yearly inspection, going back and forth between cat and downpipes every year is too cumbersome for me. Plus my end target is around 450 horsepower at the engine and I can make that easily with cats.

Do they sniff your exhaust during the yearly inspection?

 

[Armando1969]

Do they sniff your exhaust during the yearly inspection?

I should be so lucky, they measured the Exhaust fumes.

 

[Dumaurier7]

Hi, what diameter pipe is that? 2.5' ? looks GREAT by the way, I am planning on doing something similar, but I'll be replacing the mufflers too.

 

[Armando1969]

Hi, what diameter pipe is that? 2.5' ? looks GREAT by the way, I am planning on doing something similar, but I'll be replacing the mufflers too.

60mm, the same as the connection on the standard mufflers, in inch that is 2,35inch.

 

[pbondar]

Wonder why the OE pipe is squashed…the new pipe isn’t….clearance OK?

 

[Armando1969]

Wonder why the OE pipe is squashed…the new pipe isn’t….clearance OK?

I think it's for sound emissions regulations, this way most of the Exhaust gasses go through the left (bigger) muffler. And yes the clearance is okay, we fitted everything on the car and checked 3 times before we welded everything together.

 

[Dumaurier7]

60mm, the same as the connection on the standard mufflers, in inch that is 2,35inch.

I think I’ll go with the Becker and be done with it!

 

[pbondar]

Going for the full Fox system on my 35is ..pulled the trigger today

 

[Dumaurier7]

What system is that? Never heard of, can you post a link? I’d like to be able to consider all my options before I pull the trigger. I already bought a pair of DAW flow max + turbos and a PFS POD, VRSF 7.5” race IC, charge pipes etc! wanna make sure those turbos are comfortable!

 

[Armando1969]

What system is that? Never heard of, can you post a link? I’d like to be able to consider all my options before I pull the trigger. I already bought a pair of DAW flow max + turbos and a PFS POD, VRSF 7.5” race IC, charge pipes etc! wanna make sure those turbos are comfortable!

My X-pipe is part of the fox system, you can ad the mufflers, picture is below. But then you lose the flap-system that is in the standard mufflers to quiete the Exhaust sound down.

sDrive 35i, Fox Sportauspuff Shop

Fox Sportauspuff Shop - Ihr Profi für Sportauspuffanlagen aus Edelstahl

www.fox-sportauspuff.de

 

[Dumaurier7]

Their products look high quality but are a bit expensive!