euro headers w/no tune or relocation

[Beedub]

i dont get where you guys are hearing rasp, im on stock euro headers, stock mid section and ss xpipe and RPI mufflers, i hear NO rasp at all and it never did rasp???

(VT1 in this clip)

(again vt1 in this clip)

vt2 has completely changed the exhaust note "on boost".... i will grab my first video this saturday as im on the track this weekend for the first time with vt2

i dont quite understand why you guys are experiencing rasp....???

[ZStig]

I think that actually confirms that the EURO stock section 1, or x-pipe is differently designed, likely more restrictive, to reduce rasp when paired with euro headers

[inTgr8r]

Originally Posted by Beedub

i dont get where you guys are hearing rasp, im on stock euro headers, stock mid section and ss xpipe and RPI mufflers, i hear NO rasp at all and it never did rasp???
.....
i dont quite understand why you guys are experiencing rasp....???

I think the difference is in our section 1.
The CATs in our section 1 are much smaller than the Euro CATs

:edit:
lol, you beat me to it RW

[ZStig]

even though many sources say we all have the same section one. I think our section one cats have a hollow section in the middle, while the stock euro ones are full. IN YOUR FACES "MANY SOURCES"!

[Beedub]

tom the parts numbers for the us and euro X pipe are identical????? install issues maybe??
Dont forget the euro section 1 has high flow cats aswell and its a really nicely designed piece, having spent alot of time with these off the car it would really take a a good company to design a better cat section imo.

[ZStig]

its a conspiracy!

[inTgr8r]

Originally Posted by Beedub

tom the parts numbers for the us and euro X pipe are identical????? install issues maybe??
...

I find that strange.
They are definitely different pieces.
The Euro section comes c/w secondary bungs, the N.American does not.


:edit:
my bad, was thinking section1

[Beedub]

Originally Posted by inTgr8r

I find that strange.
They are definitely different pieces.
The Euro section comes c/w secondary bungs, the N.American does not.

my xpipe section doesnt have any bungs???? the mid section with the cat does for the 02 sensors but the xpipe doesnt..... ill recheck when i get home......

i have a 2007 UK car brought brand new by myself....

[ZStig]

no no, the part right ahead of the x-pipe has the connections for the 02 sensors

[inTgr8r]

Originally Posted by Beedub

my xpipe section doesnt have any bungs???? the mid section with the cat does for the 02 sensors but the xpipe doesnt..... ill recheck when i get home......

i have a 2007 UK car brought brand new by myself....

lol... reading comprehension 101

I was thinking section 1.


...yes the OE X pipe is the same on both sides of the pond

[Beedub]

Originally Posted by inTgr8r

lol... reading comprehension 101

I was thinking section 1.


...yes the OE X pipe is the same on both sides of the pond

ok thought so ;-) the xpipe is the same and the cat section is different for the euro z4m, the cell count on both the us/euro version is identical :-)

[ZStig]

Thats the thing, I think the cell count might be the same, but they're not identical if you cut them open. One is obviously hiding more rasp. That, or the muffler itself is different

someone get a hold of a BMW engineer and settle this once and for all. hahhaa

[inTgr8r]

Here's a couple of pics that makes me think the Eruo CATs are longer.

Note this Euro CAT.
Where the bungs are is the start of the fat CAT section.




US version the pipe goes much further into the heat shield until the fat CAT section

[ZStig]

the cats on the euro section definitely look longer! mystery solved?

[inTgr8r]

It would appear so.

[ZStig]

*high five

[Beedub]

are you sure this section isnt raised for the o2 bung, if you look inside the pipe the cats start at the same location ;-) Remember the 02s need to be raised up out of full exhaust flow hence theyre postion ;-) i think you guys will find the inners are the same and the outside metal has a different design to allow for the 02 bungs, the actual inner cat sections starts at the same point however ;-)

[johanness]

Originally Posted by Beedub

are you sure this section isnt raised for the o2 bung, if you look inside the pipe the cats start at the same location ;-) Remember the 02s need to be raised up out of full exhaust flow hence theyre postion ;-) i think you guys will find the inners are the same and the outside metal has a different design to allow for the 02 bungs, the actual inner cat sections starts at the same point however ;-)

I've been down this road so much on my own car, just the mention of the word O2's and CATS give me hives.
However, I think from your videos that you have the same 'rasp' or 'sound' we're all talking about. You just can't hear it over your RPI's. It's there tho.

As far as the cats are concerned... I think they're the same piece, same cell count etc. I'd love to think otherwise, but after seeing them side by side, they APPEAR the same. One with bungs, one w/o.

The real RASP culprit in my opinion is the X-pipe. That little resonator in the stocker really tones things down. Remove it, and you've got sound! Removing the primary cats in the stock headers with Euro's and you've got MORE sound! WOO

[inTgr8r]

Originally Posted by johanness

......

The real RASP culprit in my opinion is the X-pipe. That little resonator in the stocker really tones things down. Remove it, and you've got sound! Removing the primary cats in the stock headers with Euro's and you've got MORE sound! WOO

Interesting.
I'll definitely test this theory out when I do mine.

[ZStig]

drove it for 10 minutes on a wrong sized spare tire, so didn't do much full throttle runs. Anyway, sounds like I have a rattle around 3500-4000rpm, sounds like a little gattling gun. hahaah. probably needs something tightened. The throttle response is MUCH faster while revving in neutral though, it revs much more freely

Ill be selling my AFE intake for $350 shipped , if anyone wants a pre-sale jump on it