I've recently got my e30 316i on the road and I would appreciate more grunt. Ive been reading up on them and they look like what I want. I know a decat isn't going to change the power massively, it's for the sound.
Does anyone know where I can get one or is it easier to fabricate one?
decat pipe query
Moderator: martauto
they're all silenced or fitted with a cat that I know ofsweep wrote:Standard 316i m40 down pipe?
What country are you from? In the UK only the Aug '92 onwards cars had cats as standard and I think it would be mainly tourings. Any pre-92 M40 front section won't have a cat, but will have a silencer.
If it's for sound, I think you'll be disappointed... I removed the cat from my M40 and it made no difference to anything.
If it's for sound, I think you'll be disappointed... I removed the cat from my M40 and it made no difference to anything.
James
'91 325i Sport
'93 318i touring 16v
'91 325i Sport
'93 318i touring 16v
jmc330i wrote:What country are you from? In the UK only the Aug '92 onwards cars had cats as standard and I think it would be mainly tourings. Any pre-92 M40 front section won't have a cat, but will have a silencer.
If it's for sound, I think you'll be disappointed... I removed the cat from my M40 and it made no difference to anything.
it's a 94 touring
that's why I want a fabricated pipe so I can swap it overmaxfield wrote:If you're from the UK it will fail an MOT with no cat.
Just keep the cat and save yourself time, money and trouble. Removing the cat really made no difference at all on my touring.lellis wrote:that's why I want a fabricated pipe so I can swap it overmaxfield wrote:If you're from the UK it will fail an MOT with no cat.
James
'91 325i Sport
'93 318i touring 16v
'91 325i Sport
'93 318i touring 16v
- Cypriotgeeza
- E30 Zone Addict
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If your planning on doing this all just for noise why don't you just stick an induction kit on it..
Every time you floor it you'll hear it grunt

Every time you floor it you'll hear it grunt

Check my M30 build threads:
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Headgasket: viewtopic.php?f=55&t=165704
Clutch issues: viewtopic.php?f=55&t=172482
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i think you'll get a few more mpg from a decat but i'm not sure .....
E30 Touring
- Brianmoooore
- E30 Zone Team Member
- Posts: 49358
- Joined: Mon Jan 10, 2005 11:00 pm
Removing the cat. from a M40 does little for power output, but as Tommek says, will give a noticeable gain in fuel economy.
There are loopholes that can be exploited to get around the MOT test problem. The test emissions limits apply to whichever is oldest out of the engine and body, so a pre 09/91 engine will solve the problem, as will one whose age cannot be identified because the engine numbers are unreadable. Older limits also apply to any post 08/91 car fitted with a post 08/91 engine, such as any E30 with a M5x engine, or any RH drive four door or touring with a M42 engine.
There are loopholes that can be exploited to get around the MOT test problem. The test emissions limits apply to whichever is oldest out of the engine and body, so a pre 09/91 engine will solve the problem, as will one whose age cannot be identified because the engine numbers are unreadable. Older limits also apply to any post 08/91 car fitted with a post 08/91 engine, such as any E30 with a M5x engine, or any RH drive four door or touring with a M42 engine.