Z4M/S54: Euro headers installed

NLE · 08-17-2022, 11:21 PM

Reviving an old thread.

Are our oem / stock post-cat o2 sensor tables long enough to route those post-cat sensors after the secondary cats in section 1?

86Zed · 08-18-2022, 06:53 AM

Quote:

Originally Posted by NLE

Reviving an old thread.

Are our oem / stock post-cat o2 sensor tables long enough to route those post-cat sensors after the secondary cats in section 1?

Yes, it requires opening the wiring loom and re-routing down the driver side of the transmission tunnel vs the stock passenger side configuration. Documented in this thread here, can check out these videos as well from another forum member

NLE · 08-22-2022, 12:31 PM

Is there any downside to running catless headers without a tune and keeping the CEL (aka any lack of performance or harm)? Seems like the CEL cannot be coded out easily like the e46 M3 and will require an actual tune or custom tune.

Alternatively, what's the go to tune to just get rid of the CEL for catless headers?

Steeler · 08-22-2022, 01:19 PM

Quote:

Originally Posted by NLE

Alternatively, what's the go to tune to just get rid of the CEL for catless headers?

Severn Tuning will find power for you with any modification from stock.

CEL should not be an issue to code out either.

NLE · 08-22-2022, 02:17 PM

Quote:

Originally Posted by Steeler

Severn Tuning will find power for you with any modification from stock.

CEL should not be an issue to code out either.

Can you share more details on how the CEL can be coded out without actually using a tune?

Steeler · 08-22-2022, 02:19 PM

I mislead I guess with my statement.

As part of a tune only.

pal · 09-13-2022, 09:15 AM

Quote:

Originally Posted by NLE

Is there any downside to running catless headers without a tune and keeping the CEL (aka any lack of performance or harm)? Seems like the CEL cannot be coded out easily like the e46 M3 and will require an actual tune or custom tune.

Alternatively, what's the go to tune to just get rid of the CEL for catless headers?

If you relocate the post cat O2 sensors to the cats under the car, you won't need a tune or have any codes.

08-17-2022, 11:21 PM	#45
NLE Enlisted Member 3 Rep 36 Posts Drives: BMW M3 & Z4M Join Date: Jun 2022 Location: Seattle, WA iTrader: (0)	Reviving an old thread. Are our oem / stock post-cat o2 sensor tables long enough to route those post-cat sensors after the secondary cats in section 1?
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08-22-2022, 12:31 PM	#47
NLE Enlisted Member 3 Rep 36 Posts Drives: BMW M3 & Z4M Join Date: Jun 2022 Location: Seattle, WA iTrader: (0)	Is there any downside to running catless headers without a tune and keeping the CEL (aka any lack of performance or harm)? Seems like the CEL cannot be coded out easily like the e46 M3 and will require an actual tune or custom tune. Alternatively, what's the go to tune to just get rid of the CEL for catless headers?
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08-22-2022, 02:19 PM	#50
Steeler Colonel 2429 Rep 2,704 Posts Drives: Built not Bought 04 Z4 VF Join Date: Feb 2013 Location: Kitchener Ontario Canada iTrader: (2)	I mislead I guess with my statement. As part of a tune only. __________________ W2A Intercooled Vortech V3Si, custom ducting, Alpha N, 60# Bosch,2.62 pulley, multi port WMI, Severn Tuning(pokeybritches), Tial, magnaflow,SS race muffler, 42 design,3.91LSD, H&R, Hotchkis,ST coils,Konis, Megan camber arms, AKG SS, Nylon mounts, Poly bushings, Carbon interior, CF Aero.APEX Last edited by Steeler; 08-22-2022 at 02:28 PM..
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