emissions - do i need a cat?

[R1 Indy]

im designing the exhaust system for my 7, now do i need a cat or not?

just looking at pictures, very few actually have a cat fitted.

is this a case of they have been removed after test, or is it possible to pass without?


the engine is a 2008 R1, and will probably be on a Q plate.

cheers

[Russ Bost]

No way will you pass the Bets test without a CAT - what you don't need tho' is a Lambda sensor, providing you have a Power Commander or similar to map the engine correctly for idle & fast idle tests.
CATs seem to have a habit of falling off cars shortly after test!

[dave de roxby]

Would this do?

[Nedz]

You just need a good mate whos an MOT tester !!

[Russ Bost]

Sorr, just realised - not clear from your post, are you talking about passing IVA or subsequent mot tests 3 years later - it's a very different Q/A

[R1 Indy]

yes its iva im interested in.

so i take it i will need the cat for this, but can take it off after?

didn't realise that i don't need the lambda sensor though, as i will be using power commander.

[robcollingridge]

You need to check what emissions test you need to pass. It WILL be a strict modern one though and you will need a catalyst. I've got a 2003 R1 engine in my Fury and it was difficult to get through SVA and still is an issue at MOT time.

I borrowed and exhaust (with cat) and power commander map for the SVA test. I passed more by luck than judgement. Still not sure how.

Passed first MOT last year using a bespoke exhaust silencer and catalyst I had made up for me. I Spent some money getting the map optimised with an exhaust gas analyser for the MOT. It is very close but it passes, if and only if I use the idle screw to set the rpm for the fast idle test. There is no way you can keep the engine speed steady enough using the throttle pedal.

[Russ Bost]

For IVA you will need to pass the BETS test, IIRC it's 0.2% CO, <200 ppm HC's & Lamda between .97 - 1.03 but check the IVA manual links in the sticky at the top of this post. If you have power commander you will need to set up a map which leans the engine off significantly at the idle & fast idle settings. Use the fast idle screw to keep the rpm constant at around 12-1300 for idle & 27-2800 for fast idle, make sure the sensor pipe stays right up inside the exhaust as otherwise Oxygen bleeds in & screws up the lambda reading - the testers aren't always too alert to this! I would get a basic map sorted at a local friendly MoT stattion, but take your lappie & Power Commander software with you in case the IVA machine disagrees with the MoT stations.
As I say providing you set the map correctly no lambda sensor will be neccessary, but a CAT most certainly will. As regards removing the CAT afterwards, obviously has to be your decision, but if you have a Q reg you'll only need to meet visible smoke, no emissions regs for MoT certainly, if you get an age related it should state on the V5 what emissions you have to meet, if you were stopped at a roadside VOSA check this is the standard you'd be expected to meet.