Another sports/decat question

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boost monster
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Another sports/decat question

Post by boost monster » Mon Oct 08, 2018 8:06 am

I have done some research but still unsure on some things.
I want a sports cat for my M135 to give me a little more noise and hopefully a few horses, I thought I had nothing more to do the purchase,fit and enjoy.
However research revealed EML and possible MOT failures?
I do NOT have a jb4 but have a Steinbauer tuning box and don’t want to change it, but realise I might have to get the 02 sensor turned off with a map.
I wanted a sports cat to save swapping at MOT time but if there a chance of not passing emissions I may as well get a decat and save some £££ and get more noise and increased responce and swap.

So a few questions.
Will BimmerLink turn off a EML light?
Who has one (which make) and does it pass emission tests? and EML light? although this seems a lottery.
Has anyone swapped it themselves? How long does it take? I have access to a ramp anytime I want.

I need to decide as this is my Xmas present to myself 😁
M135| white|coral leather|auto|adaptive|HK |park assist|pro nav| sunroof | adaptive lights | heated memory seats | reversing camera |M performance brakes | M performance exhaust | black grills |stienbaurer power box | Eibach pro | 12 &10 mm spacersi

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NISFAN
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Re: Another sports/decat question

Post by NISFAN » Mon Oct 08, 2018 8:44 am

Your Christmas present could be to invalidate the insurance you are paying for and to make your car illegal to use on the road. Wow, what a treat!

There are sports cats that do pass MOT, but personally don’t understand why someone would put a decat /sports cat on a car for the negligible power difference it makes. I’d much rather have a car that handles better. Buy new coil overs, they’ll make a much bigger difference to your driving enjoyment. Trust me.


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Bmw_ire_2012
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Re: Another sports/decat question

Post by Bmw_ire_2012 » Mon Oct 08, 2018 9:15 am

NISFAN wrote:
Mon Oct 08, 2018 8:44 am
Your Christmas present could be to invalidate the insurance you are paying for and to make your car illegal to use on the road. Wow, what a treat! Image

There are sports cats that do pass MOT, but personally don’t understand why someone would put a decat /sports cat on a car for the negligible power difference it makes. I’d much rather have a car that handles better. Buy new coil overs, they’ll make a much bigger difference to your driving enjoyment. Trust me.


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Isn't sports CAT's fine, I have the power-valve one on my car ?
M240i Loaded With Options & M Performance Parts. Jb4 / Led M Performance Wheel / Bcs Full System - Sports Cat / BMW M Performance 624 Wheels :evil:

Blind Pugh
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Re: Another sports/decat question

Post by Blind Pugh » Mon Oct 08, 2018 9:18 am

Bmw_ire_2012 wrote:
Mon Oct 08, 2018 9:15 am
NISFAN wrote:
Mon Oct 08, 2018 8:44 am
Your Christmas present could be to invalidate the insurance you are paying for and to make your car illegal to use on the road. Wow, what a treat! Image

There are sports cats that do pass MOT, but personally don’t understand why someone would put a decat /sports cat on a car for the negligible power difference it makes. I’d much rather have a car that handles better. Buy new coil overs, they’ll make a much bigger difference to your driving enjoyment. Trust me.


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Isn't sports CAT's fine, I have the power-valve one on my car ?
I had BCS sports cat DP with lambda spacer - eventhough I had Jb4, with Jb4 off [when wife drove the car] no CEL
Fettled M135i EB AT - gone but not forgotten !
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Bmw_ire_2012
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Re: Another sports/decat question

Post by Bmw_ire_2012 » Mon Oct 08, 2018 9:31 am

Blind Pugh wrote:
Mon Oct 08, 2018 9:18 am
Bmw_ire_2012 wrote:
Mon Oct 08, 2018 9:15 am
NISFAN wrote:
Mon Oct 08, 2018 8:44 am
Your Christmas present could be to invalidate the insurance you are paying for and to make your car illegal to use on the road. Wow, what a treat! Image

There are sports cats that do pass MOT, but personally don’t understand why someone would put a decat /sports cat on a car for the negligible power difference it makes. I’d much rather have a car that handles better. Buy new coil overs, they’ll make a much bigger difference to your driving enjoyment. Trust me.


Sent from my iPhone using Tapatalk
Isn't sports CAT's fine, I have the power-valve one on my car ?
I had BCS sports cat DP with lambda spacer - eventhough I had Jb4, with Jb4 off [when wife drove the car] no CEL
I get the CEL light, I just use the jb4 to switch it off. A sports CAT isn't illegal is it?
M240i Loaded With Options & M Performance Parts. Jb4 / Led M Performance Wheel / Bcs Full System - Sports Cat / BMW M Performance 624 Wheels :evil:

Blind Pugh
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Re: Another sports/decat question

Post by Blind Pugh » Mon Oct 08, 2018 9:58 am

Bmw_ire_2012 wrote:
Mon Oct 08, 2018 9:31 am
Blind Pugh wrote:
Mon Oct 08, 2018 9:18 am
Bmw_ire_2012 wrote:
Mon Oct 08, 2018 9:15 am


Isn't sports CAT's fine, I have the power-valve one on my car ?
I had BCS sports cat DP with lambda spacer - eventhough I had Jb4, with Jb4 off [when wife drove the car] no CEL
I get the CEL light, I just use the jb4 to switch it off. A sports CAT isn't illegal is it?
If car passes mot - with sport cat DP in place - then it’s fine from a road-worthiness perspective ie emissions OK, visual inspection OK and no CEL.
Fettled M135i EB AT - gone but not forgotten !
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boost monster
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Re: Another sports/decat question

Post by boost monster » Mon Oct 08, 2018 10:05 am

Bmw_ire_2012 wrote:
Mon Oct 08, 2018 9:31 am
Blind Pugh wrote:
Mon Oct 08, 2018 9:18 am
Bmw_ire_2012 wrote:
Mon Oct 08, 2018 9:15 am


Isn't sports CAT's fine, I have the power-valve one on my car ?
I had BCS sports cat DP with lambda spacer - eventhough I had Jb4, with Jb4 off [when wife drove the car] no CEL
I get the CEL light, I just use the jb4 to switch it off. A sports CAT isn't illegal is it?
Did the car pass the mot with the bcs fitted?
M135| white|coral leather|auto|adaptive|HK |park assist|pro nav| sunroof | adaptive lights | heated memory seats | reversing camera |M performance brakes | M performance exhaust | black grills |stienbaurer power box | Eibach pro | 12 &10 mm spacersi

Bmw_ire_2012
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Re: Another sports/decat question

Post by Bmw_ire_2012 » Mon Oct 08, 2018 10:17 am

boost monster wrote:
Mon Oct 08, 2018 10:05 am
Bmw_ire_2012 wrote:
Mon Oct 08, 2018 9:31 am
Blind Pugh wrote:
Mon Oct 08, 2018 9:18 am


I had BCS sports cat DP with lambda spacer - eventhough I had Jb4, with Jb4 off [when wife drove the car] no CEL
I get the CEL light, I just use the jb4 to switch it off. A sports CAT isn't illegal is it?
Did the car pass the mot with the bcs fitted?
My cars only two years old this month hasn't been for an MOT, so I won't know until it's due. Hopefully, everything should be fine, I've got the full BCS system with their sports CAT fitted.
M240i Loaded With Options & M Performance Parts. Jb4 / Led M Performance Wheel / Bcs Full System - Sports Cat / BMW M Performance 624 Wheels :evil:

Blind Pugh
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Re: Another sports/decat question

Post by Blind Pugh » Mon Oct 08, 2018 11:00 am

boost monster wrote:
Mon Oct 08, 2018 10:05 am
Bmw_ire_2012 wrote:
Mon Oct 08, 2018 9:31 am
Blind Pugh wrote:
Mon Oct 08, 2018 9:18 am


I had BCS sports cat DP with lambda spacer - eventhough I had Jb4, with Jb4 off [when wife drove the car] no CEL
I get the CEL light, I just use the jb4 to switch it off. A sports CAT isn't illegal is it?
Did the car pass the mot with the bcs fitted?
Yes - my car passed MOT in years 3 and 4 with BCS DP in situ.
Fettled M135i EB AT - gone but not forgotten !
AW M2 DCT

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NISFAN
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Another sports/decat question

Post by NISFAN » Mon Oct 08, 2018 11:11 am

Bmw_ire_2012 wrote:
NISFAN wrote:
Mon Oct 08, 2018 8:44 am
Your Christmas present could be to invalidate the insurance you are paying for and to make your car illegal to use on the road. Wow, what a treat! Image

There are sports cats that do pass MOT, but personally don’t understand why someone would put a decat /sports cat on a car for the negligible power difference it makes. I’d much rather have a car that handles better. Buy new coil overs, they’ll make a much bigger difference to your driving enjoyment. Trust me.


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Isn't sports CAT's fine, I have the power-valve one on my car ?
Depends how you look at it......as BP says above, if it passes emissions then MOT wise all ok.
However, there is a law that prohibits tampering with emission control equipment. As a sports cat is not as good as the OE cat, you could come to the conclusion that the emission standards has been tampered with. It is a grey area, but I suspect that the number of people running around with full decats will bring the authorities to end any leeway we have. Ruining it for the rest of us.

In terms of any performance/noise it goes like this:

Decat > Sports cat > OE cat

So putting legality aside, from a performance POV I can see the attraction of the cheaper decat. I don’t really understand the small gains and high price to go from OE to sports cat on anything other than a highly tuned already car.


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Re: Another sports/decat question

Post by Wingy » Mon Oct 08, 2018 11:15 am

I had BCS sports cat on my PWG M135i and would throw the EML light every now and then but JB4 would sort it. Brought a sensor spacer but mere got round to installation. Also had an MOT with no emissions issues.
On a side note it’s arguable how much a bhp a sports cat alone gives you. But definitely allowed the car to breath and rev freely and gave a nice noise increase.

I still have the cat and JB4 sitting in a box if anyone fancies a second hand one for an early PWG model. £200 + P&P and the JB4 too £150 + P&P.


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Blind Pugh
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Re: Another sports/decat question

Post by Blind Pugh » Mon Oct 08, 2018 11:29 am

NISFAN wrote:
Mon Oct 08, 2018 11:11 am
So putting legality aside, from a performance POV I can see the attraction of the cheaper decat. I don’t really understand the small gains and high price to go from OE to sports cat on anything other than a highly tuned already car.
N'fan - my car was running JB4 custom map 6 with other bolt-ons ~ +90/150 power/torques which was not achievable reliably with OEM DP in situ.

I don't do decats for 2 reasons - road-worthiness and sound - latter is to raspy for my old ears. BCS 200CPI worked well and given larger cat body, losses compared to deact are minimal.

2 benefits of ditching OEM DP for either sport cat or decat DP are, IMHO:-

- gains - whilst I agree with N'fan peak gains maybe minimal but even on stock engine gains post DP swap across the rev range ie area under the curve will be there to improve driveability;
- throttle response. Even on a std car, switching from a OEM 600CPI DP to either 200CPI or less DP reaps huge gains - turbo spools up quicker and likely to hold boost targets longer and more consistently as result.
Fettled M135i EB AT - gone but not forgotten !
AW M2 DCT

boost monster
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Re: Another sports/decat question

Post by boost monster » Mon Oct 08, 2018 6:39 pm

Wingy wrote:
Mon Oct 08, 2018 11:15 am
I had BCS sports cat on my PWG M135i and would throw the EML light every now and then but JB4 would sort it. Brought a sensor spacer but mere got round to installation. Also had an MOT with no emissions issues.
On a side note it’s arguable how much a bhp a sports cat alone gives you. But definitely allowed the car to breath and rev freely and gave a nice noise increase.

I still have the cat and JB4 sitting in a box if anyone fancies a second hand one for an early PWG model. £200 + P&P and the JB4 too £150 + P&P.


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