Z4m Exhaust to 3.0si Possible???

[Ivesy]

Anyone know if its possible to mate a z4m dual exhaust to the cats on a 3.0si? Really want a dual exhaust... Thanks.

[grannyknot]

I think you will find that your battery box will be in the way of the right side muffler.

[wdb]

You can't use a Z4M exhaust without a TON of rework. So much so that you may as well just buy the M car. There is another way to get dual exhaust tips though.

https://www.bimmerworld.com/Exhaust/...-Aero-Kit.html

[Piper1]

Super sprint also has an option but you need the Y pipe section fitted too which that comes with from Turner, there are sleeves if not using any other part of Supersprint that adapts the Y to the stock diameter. https://www.turnermotorsport.com/p-6...n-4x80mm-tips/
Either of those are still on my list but few other things first.

[grannyknot]

Originally Posted by wdb

You can't use a Z4M exhaust without a TON of rework. So much so that you may as well just by the M car. There is another way to get dual exhaust tips though.

https://www.bimmerworld.com/Exhaust/...-Aero-Kit.html

Whoa, $2,200 for a muffler and what looks like plumbing pipes?
No offence meant wdb, it always just blows me away how much BMW tax is slapped on things.

Ivesy , You could take that picture of the Eisenmann exhaust to your local muffler shop and I'm sure they could put something together that would be very similar for a lot less $

[wdb]

It's as much an Eisenmann tax as anything. I had Eisenmann cans on my Z4MC. Very, very nice noise.

[Ivesy]

Thanks a lot for the input guys. I have seen Si's with dual setups but I guess they are this strange one branch thing with the right hand section. Seems a bit fake to me, like it might only blow out of one section and be totally pointless.. So from what I'm hearing the battery box in the boot will scupper my plan for a true dual setup. I will see if I can find a local exhaust maker to help. Thanks again.

[CJW2OO4]

The RPI exhaust is the smallest “mufflers” you can get for the Z4M. Perhaps that may be a starting point for you.

I found a comparison picture. You can see the drastic size difference. These RPIs we’re painted as they don’t come in black.

[Piper1]

Originally Posted by Ivesy

Thanks a lot for the input guys. I have seen Si's with dual setups but I guess they are this strange one branch thing with the right hand section. Seems a bit fake to me, like it might only blow out of one section and be totally pointless.. So from what I'm hearing the battery box in the boot will scupper my plan for a true dual setup. I will see if I can find a local exhaust maker to help. Thanks again.

There’s been some fab work like this:

https://www.zpost.com/forums/showthread.php?t=529926

Or to route this to the other side on one pipe
https://www.zpost.com/forums/showthread.php?t=687247

Scroll to the bottom of this thread and you’ll see another custom route which simply puts a dual tip on one outlet on the muffler and a 90deg bend on the other outlet then running the pipe to the rh side.

https://z4-forum.com/forum/viewtopic...28955&start=45

On the z4-forum uk based boards someone reworked a different battery and went through all the fab work to make a true dual but it was a good bit of work for what performance gained imo.

https://z4-forum.com/forum/viewtopic.php?f=27&t=10723

At the end of the day though from fab/to install and all headaches in between it’s more all show anyway. In a blind taste test you’re just not going to be able to feel the difference without doing more such as least a tune or F/I, full exhaust including headers. Look at the new Supra. There’s a shut off value when not in sport so only one side of the dual is actual spitting out fumes.

But the piping inside the main box on eisenmann and supersprint route to the other side so it’s not going to have a point where exhaust fumes don’t come out.

Here’s under pic of the eisenmann in this thread
https://z4-forum.com/forum/viewtopic...27265&start=15

[Ivesy]

Originally Posted by Piper1

There’s been some fab work like this:

https://www.zpost.com/forums/showthread.php?t=529926

Or to route this to the other side on one pipe
https://www.zpost.com/forums/showthread.php?t=687247

Scroll to the bottom of this thread and you’ll see another custom route which simply puts a dual tip on one outlet on the muffler and a 90deg bend on the other outlet then running the pipe to the rh side.

https://z4-forum.com/forum/viewtopic...28955&start=45

On the z4-forum uk based boards someone reworked a different battery and went through all the fab work to make a true dual but it was a good bit of work for what performance gained imo.

https://z4-forum.com/forum/viewtopic.php?f=27&t=10723

At the end of the day though from fab/to install and all headaches in between it’s more all show anyway. In a blind taste test you’re just not going to be able to feel the difference without doing more such as least a tune or F/I, full exhaust including headers. Look at the new Supra. There’s a shut off value when not in sport so only one side of the dual is actual spitting out fumes.

But the piping inside the main box on eisenmann and supersprint route to the other side so it’s not going to have a point where exhaust fumes don’t come out.

Here’s under pic of the eisenmann in this thread
https://z4-forum.com/forum/viewtopic...27265&start=15

Thanks a lot for all of that! Yep, it's almost definitely not worth it. Looks great though.