Custom Exhaust Pipes - What would you do

[Defratos]

So I finally received my Greddy Titanium Exhaust....it's a work of art but realized that I won't be road legal in the UK with these fitted as I'm also running PPE Headers, so I need to install Cats somewhere.

Instead of mutilating the beautiful titanium exhaust I'll have to sacrifice the pipes connected to the headers and build a custom stainless steel replica of the pipes below..

The question I have is how would you go about installing the cats.

- Option one would be to make a replica of the pipes with resonators and install the cats in the area highlighted in Yellow below.

- Option two would be to have no resonators and simply install the cats in the same location as the resonators circled in red.

So Do I get the exhaust shop to install resonators and Cats, or simply just cats in the same location of the resonators below?

Any help would be appreciated.

 

[Jgtcracer]

Easy, remove resonators and install cats there!!  

No such thing as a V8 that is too loud!!!

[Big Rat]

I could be wrong and I agree with Marcus suggestion, but don’t the cats have to be as close as possible to the upstream to be effective ?

Bug Rat

[Big Rat]

1 hour ago, Defratos said:

So I finally received my Greddy Titanium Exhaust....it's a work of art but realized that I won't be road legal in the UK with these fitted as I'm also running PPE Headers, so I need to install Cats somewhere.

Instead of mutilating the beautiful titanium exhaust I'll have to sacrifice the pipes connected to the headers and build a custom stainless steel replica of the pipes below..

The question I have is how would you go about installing the cats.

- Option one would be to make a replica of the pipes with resonators and install the cats in the area highlighted in Yellow below.

- Option two would be to have no resonators and simply install the cats in the same location as the resonators circled in red.

So Do I get the exhaust shop to install resonators and Cats, or simply just cats in the same location of the resonators below?

Any help would be appreciated.

 

@Defratos Oooh nice spangly bits, can’t wait to see/hear the vid !

🐀

 

[Martin F]

1 hour ago, Big Rat said:

I could be wrong and I agree with Marcus suggestion, but don’t the cats have to be as close as possible to the upstream to be effective ?

Bug Rat

Yes, they do as they need to be at a certain temperature to work. 

[Big Rat]

26 minutes ago, Martin F said:

Yes, they do as they need to be at a certain temperature to work. 

@Martin F Thanx for that matey just going to mention it to Mrs Rat, that I can be right..........

🐀

[Guest]

Wrap the pipe all the way the pipe all the way to the c;at to keep the heat in.

We might be removing them one day, you never know

Quote

One problem is that they only really work at high temperatures (over 300°C/600°F or so), when the engine has had chance to warm things up, which might take 10–15 minutes. So they are ineffective for the first part of a journey (or any part of a very short journey).

Another issue is whether they increase greenhouse gas emissions. We think of carbon dioxide as a safe gas, because it's not toxic in everyday concentrations. Nevertheless, it isn't entirely harmless, because we now know it's the major cause of global warming and climate change. Some people believe catalytic converters make climate change worse because they turn carbon monoxide into carbon dioxide. In fact, the carbon monoxide your car produces would eventually turn into carbon dioxide in the atmosphere all by itself, so a catalytic converter makes no difference on that score: it simply reduces the carbon monoxide a car pumps into the street as it drives along, improving the local air quality.

But when it comes to climate change, auto engineers and environmentalists have long pointed out another serious issue. Although cats turn most nitrogen oxides into nitrogen and oxygen, they also produce small amounts of nitrous oxide (N2O) in the process, a greenhouse gas that's over 300 times more potent than carbon dioxide. The trouble is that with so many vehicles on the road, even small amounts of nitrous oxide add up to a major problem. Back in 2000, the Intergovernmental Panel on Climate Change noted: "The introduction of catalytic converters as a pollution control measure in the majority of industrialized countries is resulting in a substantial increase in N2O emissions from gasoline vehicles." Fortunately, newer catalytic converters produce dramatically less nitrous oxide than older ones. Even so, while catalytic converters have certainly helped us to tackle short-term air pollution, there are concerns that, when it comes to long-term climate change, they could be making matters worse.

 

[Ace8800]

Depends how loud you want it.. personally i would leave the res and fit cats, see how loud it is and if you want it louder then chop the res off later.

[Defratos]

3 hours ago, Jgtcracer said:

Easy, remove resonators and install cats there!!  

No such thing as a V8 that is too loud!!!

lol I wouldn't completely agree on a V8 not being too loud, I've heard some seriously horrible V8 exhausts and I don't want something that I can't drive Daily. 

 

2 hours ago, Big Rat said:

I could be wrong and I agree with Marcus suggestion, but don’t the cats have to be as close as possible to the upstream to be effective ?

Bug Rat

Thanks for the reply, well in that case I could always put them before the sensors....so basically right after the headers/exhaust flang and before the sensors which is what one person did in CL and another put them further down the exhaust. --> (https://www.clublexus.com/forums/is-f-2008-2014/838978-magnaflow-vs-gesi-cats.html)

 

I basically I want my car to pass MOT test, does MOT also have a noise specification in place? i.e. how loud my exhaust can be? if so then I'll probably need cats and resonators together.

[Defratos]

Just now, Ace8800 said:

Depends how loud you want it.. personally i would leave the res and fit cats, see how loud it is and if you want it louder then chop the res off later.

Sounds like a logical route to take. 

[Jgtcracer]

3 hours ago, Big Rat said:

I could be wrong and I agree with Marcus suggestion, but don’t the cats have to be as close as possible to the upstream to be effective ?

Bug Rat

In all seriousness, Big Rat is right, hour temps tend to be better.  I love my cars loud but as said below, if you for as well as resonators at least you can remove them if it's still too quiet.  

Don't think there is a sound limit but on a little saxo or corsa the police could do you for antisocial behaviour.

[Warrington guy]

I think anything to do with exhaust’s flytvr is your man 

[Big Rat]

@Warrington guy Nah @Flytvr it's just a 'pipe' dream of his 😁

🐀

[Warrington guy]

Big rat . Flytvr must be out waking all the neighbours up

[Big Rat]

@Warrington guy Dave let's just hope he's got a mile wide smile otherwise his search may continue............... so if you go out to yours one night and the system is missing you will know where to start the search 

🐀

[Pecker]

The drone from having no cats is bad... 2k rpm it's unbearable for a daily driver as I learnt from experience. I know a man with some new Magnaflow high flow cats if you need em...

[Defratos]

Thanks Pecker, I've already got a pair of GESI Cats with me which should deal with the abuse better than Magnaflow. 

 

I also have a pair of Magnaflow cats that I'm trying to sell lol.

 

Does anyone know where I can source some Titanium Catalytic converters? I've found titanium resonators but now I want some titanium cats to see if I can build these pipes out of titanium rather than SS.