MOT Failure due to exceeding emissions limits

biZ4rreMids · Post by **biZ4rreMids** » Thu Oct 07, 2021 6:13 pm

Last year I had my 20i remapped along with the installation of a supersprint decat pipe and a Wagner intercooler which resulted in 281bhp and 450nm of torque. Today the car failed the MOT due to exceeding the emissions test limits.

Fortunately I kept the original catalytic converter and this was fitted today and although the car still performs well it has lost its roar. Emissions results with the supersprint decat pipe fitted and with the catalytic converter fitted below for your perusal.

B21 · Post by **B21** » Thu Oct 07, 2021 6:24 pm

Yup..with the N20 fitted to the E89 with the only cat hanging of the exhaust that’s what you get..

Now of course, the solution is a sports cat, AFAIK, only Evolution Works provides a 200 cell sports cat that will pass a UK MOT..

I just happen to have one…(the sound of a vulture crowing )…great sound..arguably better than the empty tin can that you have

biZ4rreMids · Post by **biZ4rreMids** » Thu Oct 07, 2021 9:30 pm

Went for a quick hoon this afternoon and decided to reinstall the decat pipe as I’m missing the growl on acceleration and the burbles/pops on manual downshifts. Not missing the smelly bottom though

B21 · Post by **B21** » Thu Oct 07, 2021 9:56 pm

biZ4rreMids wrote: ↑Thu Oct 07, 2021 9:30 pm Went for a quick hoon this afternoon and decided to reinstall the decat pipe as I’m missing the growl on acceleration and the burbles/pops on manual downshifts. Not missing the smelly bottom though

If your happy to swap over cans for the MOT then that’s a solution….

Personally I found the noise a bit too chavy but each to their own

BeardyJon · Post by **BeardyJon** » Fri Oct 08, 2021 11:46 am

The supersprint pipe that you fitted... is it this one?

I've had the car remapped with a Celtic stage 3 map, and I want to delete the resonator, but keep the back box & stock downpipes. Sounds quite similar to what you've done, is that right? Just wondering if I should even bother if I'm gonna fail every MOT by doing that.

Smartbear · Post by **Smartbear** » Fri Oct 08, 2021 2:08 pm

BeardyJon wrote: ↑Fri Oct 08, 2021 11:46 am The supersprint pipe that you fitted... is it this one?

I've had the car remapped with a Celtic stage 3 map, and I want to delete the resonator, but keep the back box & stock downpipes. Sounds quite similar to what you've done, is that right? Just wondering if I should even bother if I'm gonna fail every MOT by doing that.

This is what an N20 decat pipe looks like

: 5A718E28-5B83-46A7-BAF7-5CBD86BCD7E9.png (213.39 KiB) Viewed 379 times

Rob

biZ4rreMids · Post by **biZ4rreMids** » Fri Oct 08, 2021 5:07 pm

Smartbear wrote: ↑Fri Oct 08, 2021 2:08 pm
BeardyJon wrote: ↑Fri Oct 08, 2021 11:46 am The supersprint pipe that you fitted... is it this one?

I've had the car remapped with a Celtic stage 3 map, and I want to delete the resonator, but keep the back box & stock downpipes. Sounds quite similar to what you've done, is that right? Just wondering if I should even bother if I'm gonna fail every MOT by doing that.
This is what an N20 decat pipe looks like
5A718E28-5B83-46A7-BAF7-5CBD86BCD7E9.png
Rob

As per Smartbears post above. Supersprint produce a full sports exhaust too which your photo shows part of.

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