Catted Mid pipe project

[JD001]

Emission checks in the UK are pretty stringent. I have a aftermarket UEL (no cat) and fast flow cat in the aftermarket front pipe. I have been running this for 4 odd years, over the past 3 years the car has been tested annually for emissions... no issues.

[wparsons]

Originally Posted by Wil

Don't worry, I know the exhaust like my pocket, ahah!
I mean, would adding a 100/200-cell cat after the second cat do the trick?

I don't care if the care smells when it warms up. As long as, when it's warm, the smell is gone, then mission accomplished.

But would I benefit from the added performance of a catless header? Just by "moving" the first cat down the line and swapping it for a sportier one?

Supercharging... I would love that! But hey, this is Belgium...
Change your rims and you won't pass inspection. That's half true though.

I'm confused... are you still getting the catless smell with the stock secondary cat in place? You really shouldn't be.

[Irace86.2.0]

Originally Posted by wparsons

I'm confused... are you still getting the catless smell with the stock secondary cat in place? You really shouldn't be.

^^^This.

OP, maybe there would be smell on startup, but the precat is there to heat the main cat. It doesn’t do much more than that. In fact, it is mainly there for startup when the main cat is cold, and potentially at low speeds or idling situations in cold weather.

https://www.roadandtrack.com/new-car...ent-explained/

The precat isn’t even needed for good emissions once the car is warm. It begs the question why wouldn’t an electrical heater like a block warmer be a better solution than even the Koenisegg’s solution.

[Wil]

Would a cerakoted header partially solve the issue?

[Vital]

Originally Posted by Wil

Would a cerakoted header partially solve the issue?

Cerakoting the header has nothing to do with Cats...those are two separate things.

[Timmy_Jones]

Whats the EU punishment for being caught tampering with the cat and exhaust? Honestly doesnt sound worth tampering with the exhaust at all.

[mrg666]

Originally Posted by Irace86.2.0

^^^This.

OP, maybe there would be smell on startup, but the precat is there to heat the main cat. It doesn’t do much more than that. In fact, it is mainly there for startup when the main cat is cold, and potentially at low speeds or idling situations in cold weather.

https://www.roadandtrack.com/new-car...ent-explained/

The precat isn’t even needed for good emissions once the car is warm. It begs the question why wouldn’t an electrical heater like a block warmer be a better solution than even the Koenisegg’s solution.

My understanding is that our main cat is the one on the header. that is why the oxygen sensors are attached to it. The second cat is there to help with emissions rating but it is not a requirement for running the engine.

[mav1178]

Originally Posted by Wil

I mean, would adding a 100/200-cell cat after the second cat do the trick?

The problem is catalytic converters need a minimum temperature to function.

Without testing your theory with thermal probes and datalogging the results, it's impossible for any of us to armchair and say "yes it will work".. you can wrap headers all you want but you're the only one with this idea so far.