[tej98]

Little bit of a long shot but has anyone had success putting a full N55 exhaust on an N54 car (basically everything from the downpipes back)? Wondering as I may have a chance to grab a used AFE N55 system and some initial research shows that it should work but I wanted to double check. I have an E90 if it matters.

Thanks!

[whyzee125]

Aftermarket exhausts are the same for both engines as long as it’s from e9x chassis and not f3x.

[ky0u]

Originally Posted by whyzee125

Aftermarket exhausts are the same for both engines as long as it’s from e9x chassis and not f3x.

The downpipes are not the same

[tej98]

Originally Posted by ky0u

The downpipes are not the same

So would it bolt up to the downpipes for an N54?

[whyzee125]

Originally Posted by tej98

So would it bolt up to the downpipes for an N54?

Yes. The Downpipes are obviously different but the n55 down pipe still splits into two flanges just like the N54. Totally interchangeable catbacks.

[tej98]

Originally Posted by whyzee125

Yes. The Downpipes are obviously different but the n55 down pipe still splits into two flanges just like the N54. Totally interchangeable catbacks.

Awesome, thank you so much!

[studio54]

Originally Posted by tej98

Awesome, thank you so much!

Yep midpipes are the same design N54 vs N55, except the N55 pipe don't come with secondary catalytic converters, while N54 midpipe are with cats and obviously N54 midpipe have a way higher price than N55. (It's 600 cells cats)

I believe both come with a silencer OEM.

However downpipe are not the same due to not being the same turbo setup.

It splits at the end in two for both, but for N55 the downpipe is only one entry at beginning.

[jacobniell]

Originally Posted by studio54

Yep midpipes are the same design N54 vs N55, except the N55 pipe don't come with secondary catalytic converters, while N54 midpipe are with cats and obviously N54 midpipe have a way higher price than N55. (It's 600 cells cats)

I believe both come with a silencer OEM.

However downpipe are not the same due to not being the same turbo setup.

It splits at the end in two for both, but for N55 the downpipe is only one entry at beginning.

What is 600 cell cats? is it the N54 secondary cats that is 600 or?

[studio54]

Originally Posted by jacobniell

What is 600 cell cats? is it the N54 secondary cats that is 600 or?

It's the rating (number of cells per inch square) of the catalytic converters.

It's 600 cpsi for BMW N54 (downpipes and secondary).