Hello everyone
Im new to this forum as just bought my first Z4. Its a 2004 2.5 engine. Im sure its been discussed many times but can some one send me the link to the disacussion on who to buy the kits from in UK for secondary cat delete kits.
many thanks
Not joined yet? Register for free and enjoy features such as alerts, private messaging and viewing latest posts and topics.
Z4 2.5 secondary cat delete kit
- Smartbear
- Lifer
- Posts: 13685
- Joined: Wed Feb 05, 2014 6:54 pm
- Location: a barn in Somerset
Z4 2.5 secondary cat delete kit
Hi, I’m not sure that the m54 cars even have secondary cats - i thought they had one cat in the exhaust manifold?
Rob
e89 Sdrive 20i, plenty of mumbo & good economy-the thinking bears z4
e89 Sdrive 30i, this ones busted, pass me another...
e85 3.0si sold
-
- Newbie
- Posts: 2
- Joined: Fri Dec 02, 2022 12:37 pm
Z4 2.5 secondary cat delete kit
Hi Rob
It does have the 2 cats. first ones are still present i think. i'll try to take a picture
It does have the 2 cats. first ones are still present i think. i'll try to take a picture
- TheDan
- Member
- Posts: 627
- Joined: Wed Aug 19, 2020 1:58 pm
- Location: Warwick, UK
Z4 2.5 secondary cat delete kit
Yeah there are 2 cats and 2 mufflers/resonators on the pre-facelift 6 pot exhaust. From memory I am pretty certain the right blob in the picture is the secondary cat and the middle blob is the primary resonator (and the left blob is obviously the secondary resonator/backbox). From what I've seen on here most people just get an exhaust shop to cut off one or both of the middle sections and replace with straight pipes. I have also heard that they pass the emissions MOT test fine without the secondary cat.
- Attachments
-
- Untitled.png (124.89 KiB) Viewed 323 times
- Smartbear
- Lifer
- Posts: 13685
- Joined: Wed Feb 05, 2014 6:54 pm
- Location: a barn in Somerset
Z4 2.5 secondary cat delete kit
Think I’m getting them mixed up with the n52 cars
Rob
e89 Sdrive 20i, plenty of mumbo & good economy-the thinking bears z4
e89 Sdrive 30i, this ones busted, pass me another...
e85 3.0si sold
- Sidewaze Samm
- Senior Member
- Posts: 1209
- Joined: Wed Feb 07, 2018 1:11 pm
- Location: Sth. Manchester/Cheshire border
Z4 2.5 secondary cat delete kit
It's possible to open the cover shields for the secondary cats; cut cats open; remove the gubbins; re-weld the cats; and then replace covers. If done with care all looks standard and untouched.
Sounds better though!
viewtopic.php?f=2&t=129420&hilit=cat
Sounds better though!
viewtopic.php?f=2&t=129420&hilit=cat
2008 E85 3.0si
Space Grey, Dream Red New England heated Msports.
Xenons, MFSW, cruise, PDC, wind deflector.
ZHP, stubby, gloss black grilles, DLV box, gaptech, no CDV.
Space Grey, Dream Red New England heated Msports.
Xenons, MFSW, cruise, PDC, wind deflector.
ZHP, stubby, gloss black grilles, DLV box, gaptech, no CDV.
- patriot66
- Lifer
- Posts: 3480
- Joined: Sun Jan 11, 2015 2:59 am
- Location: Mawdesley, Lancashire
Z4 2.5 secondary cat delete kit
This At 20 years old the secondary cat ceramic is absolutely shot and serving no purpose whatsoever other than to REALLY hinder gas flow. Get rid ! I did. Vastly improved throttle response and a bit more noiseSidewaze Samm wrote: ↑Fri Dec 02, 2022 9:38 pm It's possible to open the cover shields for the secondary cats; cut cats open; remove the gubbins; re-weld the cats; and then replace covers. If done with care all looks standard and untouched.
Sounds better though!
viewtopic.php?f=2&t=129420&hilit=cat
Sailed through its MOT last January with no issues at all
Sterling Grey '03 2.5i SE / Infinitas Supercharger / S.M.G / Hardtop / Gloss Black 162s / Bilstein B4s / 3.0i Brakes / DLV De-Cat & Silencer / Rebuilt VANOS / Sonar 2Xcite Lights / Carbon & Alcantara Trim / M-Sport Seats / ...& Side Covers !