[pbedrosi]

AliExpress has them again, around $220-$270 + Shipping from couple of sources.

I did find less expensive ones with lower grade staleness, 201, they say it will corrode but not sure if it matters for headers, its not a show care either.

$80 plus shipping. Also, 02 upstream bungs are in the right spot for our E91.

https://www.aliexpress.us/item/32568...yAdapt=glo2usa

[gaze2]

Originally Posted by pbedrosi

AliExpress has them again, around $220-$270 + Shipping from couple of sources.

I did find less expensive ones with lower grade staleness, 201, they say it will corrode but not sure if it matters for headers, its not a show care either.

$80 plus shipping. Also, 02 upstream bungs are in the right spot for our E91.

https://www.aliexpress.us/item/32568...yAdapt=glo2usa

Ok so, the upstream bungs on the OEM exhaust are on top, where the bank merges so the sensor catches all 3 cylinders. The cheaper aliexpress one you linked which have it on top but on only one cylinder. Although the more expensive aliexpress AA headers seem to have 2 variants one for EU market and one for NA market, and one of them also has the bung on the primary on top...
So it goes like this:

Cheap aliexpress headers:
- primary o2 bungs on top of middle cylinder primary

Expensive aliexpress headers (AA copy) Version 1:
- primary o2 bungs at the collector, next to secondary bungs

Expensive aliexpress headers Version 2 (for europe?):
- primary o2 bungs on top of middle cylinder primary

Why not make all of them have the primary bung on the collector? Why have EU and NA versions of the headers? Are the stock headers different in those regions? On realoem the headers look the same. Maybe the EU version has shorter cables and couldnt reach the bung all the way in the back or something?
I wonder with the "proper" exhaust header having the primary o2 next to the secondary, what would be the problem of just putting the primary o2 sensor in the secondary "downstream" bung on the other designs? Or just making the ECU use the secondary o2 sensor for adjusting AFR and stuff, and plugging the primary and secondary o2 sensors in their respective holes? Is that even possible?
What about the o2 sensor needing to be hot to work properly? Maybe that's why they put it so close to the exhaust valves?

I recently discovered my EU spec 325i with the n52b25 has had its cats removed, but I dont have any CEL or errors so I guess the secondary o2 sensor has been coded out or something. I am trying to figure out what to do, if the secondary o2 sensor isnt working what is stopping me from buying the cheapest header with the wrong bung positions, and just plugging in my primary o2 sensor in the downstream bung?

[Clean328]

Does anyone have an updated link to the headers? The posted one doesn't work anymore. Looking to join the crew lol

[firesnatch]

Originally Posted by Clean328

Does anyone have an updated link to the headers? The posted one doesn't work anymore. Looking to join the crew lol

The link is always changing. Just go to www.aliexpress.us and search "bmw e90 headers". Substitute e90 for e92, e93, etc depending on what car you have. Look for the product pictures showing "HZ racing parts" in red letters.

Example here

[astigpangit]

anyone know if the kungfu performance ones on Aliexpress are the same thing? they’re on sale right now. if you search n52 headers

[firesnatch]

Originally Posted by astigpangit

anyone know if the kungfu performance ones on Aliexpress are the same thing? they’re on sale right now. if you search n52 headers

Not sure, but I've heard that you should avoid the ones with the o2 sensor bung located on just one of the 3 pipes.

[WheelNut2]

Do these change the exhaust note in a significant way? Since the exhaust pulses should leave the exhaust system at totally even intervals I'd assume it would make the exhaust sound a bit higher pitched and more clear.

[astigpangit]

i just got the Kungfu Performance headers that was on the 11.11 sale for $185 plus $125 shipping, plus tax. i believe they still have similar pricing for Black Friday. looks identical to HZ racing and o2 bungs are in the right spots (after where the 3 runners merge, not on top of the runners next to where the headers bolt onto the block, like OP’s post). i did speak with the seller after i placed the order to ensure i would receive the correct version. according to someone else, these are Taimei Performance, which Roundelwerk might be dropshipping.

seller first told me to do aliexpress shipping but that was actually much more expensive at the time (washington state). they said that price changes a lot so i went with the cheapest and actually one of the fastest shipping options. it arrived in less than a week (yes it came from china).

i’ll probably get a quote from a performance coating shop for Cerakote this coming week.

just waiting for locknuts and gaskets from FCP Euro and i’ll install soon. gonna tune with 22RPD with milvs and 3sim and i’ll post back with butt dyno results.

[Clean328]

Unfortunately, the HZ Racing headers are sold out on AliExpress. I did find them on Alibaba but I have to send the seller a message first to begin the buying process and it's a bit sketchy. Has anyone bought the same headers from Alibaba?

On the other hand, it seems as though the next best thing is the KUNGFU PERFORMANCE headers on AliExpress. Which one should I roll with, lol?

KUNGFU PERFORMANCE ON ALIEXPRESS: https://www.aliexpress.us/item/32568...%3A#nav-review

HZ RACING ON ALIBABA:
https://www.alibaba.com/product-deta...16ce13a03cgm1G

[astigpangit]

Originally Posted by Clean328

Unfortunately, the HZ Racing headers are sold out on AliExpress. I did find them on Alibaba but I have to send the seller a message first to begin the buying process and it's a bit sketchy. Has anyone bought the same headers from Alibaba?

On the other hand, it seems as though the next best thing is the KUNGFU PERFORMANCE headers on AliExpress. Which one should I roll with, lol?

KUNGFU PERFORMANCE ON ALIEXPRESS: https://www.aliexpress.us/item/3256805610101604.html?spm=a2g0o.productlist.main.3 .52c257f397hFlm&algo_pvid=109b8031-b0e9-44f8-9f48-b79a159761ee&algo_exp_id=109b8031-b0e9-44f8-9f48-b79a159761ee-1&pdp_npi=4%40dis%21USD%21239.00%21193.59%21%21%21 239.00%21193.59%21%402101c72a17327774406848970e70d 5%2112000034383698235%21sea%21US%210%21ABX&curPage LogUid=VxImNuv6TGOR&utparam-url=scene%3Asearch%7Cquery_from%3A#nav-review

HZ RACING ON ALIBABA:
https://www.alibaba.com/product-detail/exhaust-header-N52-N53-128i-325i_1600214076262.html?spm=a2700.galleryofferlist .normal_offer.d_image.16ce13a03cgm1G

i have the kungfu ones. i dont have any good pics but it looks solid and the welds are nice. i haven’t installed yet though, it might be a little while since i’ll be busy for a couple weeks.

the flanges have some stainless steel finish on them which i was little turned off by, but maybe the AA or HZ racing ones are the same

[aphael]

I was one of the early buyers of the HZ racing headers at around the same time as Raimund. still going strong no cracks 40k miles later. These make your car very loud if you have a muffler delete, almost obnoxious. I'm planning on taking them off in a few months in preparation of selling the car

[Kamikazi1971]

Originally Posted by Zupplyzz

Yeah true but they don’t seem too bad, some people did leave good reviews on their website for it. Still debating whether or not I should pull the trigger on these

Hi The biggest problem for headers its bad smell cus of cat

[christian_128i]

I ended up purchasing a set of the hz headers aswell.

I noticed something unusual though upon inspecting them.

There seems to be like a yellowish glaze on the headers located on the mounting and the lower part of that connects to the midpipe.

I have attached a few images for reference.

I was wondering if anyone else experienced this.

[Ricthewrench]

Heat coloration. Nbd. Run em!