I have a V12 Vantage. Remote switch for the flaps too. Superb noice

Secondary cat is before the side long silencer.

There’s a lambda there pre 1st and post 2nd

I wonder if the BMW cars using this engine had 4 cats as well? Seems a curious setup with two back to back either bank.

Fairly standard on a big engine

Viper, given that squeezing 4 gallons (AM V12) into a thimble (V8 engine bay) along with all it's additional cooling etc is the 4 cat solution not more related to packaging? 4 little un's instead of 2 bigger un's?

Hence the sensor being over the pair of them?

Meant as a question as much as anything else.

Alistair.
You could have a point but I’m not aware of any large lumpy V engine with just one per side. Could be wrong of course.

Sensors are always pre and post. Would be pointless putting a sensor after the first thought that’s effectively what I have on the AM now.

I’m trying to build up enthusiasm to take the aero apart and send the cats off atm.

I need to have a really bored few days I think

Just watch the news, that will do it.

Have you bored yourself yet? Please say yes

No not yet. Went into the garage with goof intent and couldn’t be arsed. I’ll get there

Hahaha

I don't know how emissions inspections work in the UK, but here in the US removing catalytic converters is verboten. Tampering with any of the required emissions equipment subjects the owner to fines and suspension of the vehicle's registration. Companies that supply emissions work-arounds are receiving big fines Like this...