CAT and Exhaust

[rweir]

Guys,

Has anyone here removed the CAT and exhaust cladding etc?

Cheeers,
Rich.

[ThatPhilBrettGuy]

Do a search as I seem to remember it's been covered here not long ago. If I remember correctly the CAT's are really small and make little difference (if you're thinking of performance increases that is).

Cheers

Phil

[rweir]

It was more for the flames and some nice pops and bangs...

I was out last night 'playing' with some caterhams, when I was behind them some of them put on a good show

Rich

[ThatPhilBrettGuy]

That's a good enough reason for me! I guess it's going to depend on the map to some extent. Maybe Mr YellowShed can produce something suitable

[rweir]

Map, are you refering to an engine remap? Will it need such a thing? Assuming I am not that bothered at remaping for the little HP to be gained?

rich

[ThatPhilBrettGuy]

I was more thinking that the current map (being very good) may not run rich enough to produce many flames on overrun. I can't see the exhaust lasting long though....

Putting them back in for MOT's is going to be a pain.

[rweir]

True, but thankfully being a new car it does not need an MOT for a few years ...

Yes, I am thinking it may reduce the life of the exhaust!

I suppose the best way would be to get the cat and cladding(???) taken out and take it from there. That being the part the dealer can do for me when it is in.

Rich

[NoLimits]

What are the specs of stock exhaust inner and outer diameter from turbo back? How many cats/resonators? I am guessing two mufflers ... but of what size internally ad externally?

Are will known brands used or this considered a custom Noble exhaust system?

The flames will depend on air fuel and timing. The caterhams could have been slightly improperly tuned.

Kinda a silly thing to mod for ... but I can understand.

Shouldn't reduce life of you exhaust system at all.

The less rectriction may improve gas mileage and turbo shaft lifespan. Also, f you have no cat to replace, you don't need to worry about replacing.

For those of you worried about getting caught without tunning with a cat ... tere are electric dump setups that can be opened and closed from insude the cockpitto allow exhauyst to vent to atmoshere or past the cat and back into the exhaust down-stream if you want.

Here is one of many: www.quicktimeperformance.com/QTEC/

Search the web for more brands and maybe better bargains.

HTH.



>> Edited by NoLimits on Thursday 9th September 21:31

[ThatPhilBrettGuy]

NoLimits said:

What are the specs of stock exhaust inner and outer diameter from turbo back? How many cats/resonators? I am guessing two mufflers ... but of what size internally ad externally? Are will known brands used or this considered a custom Noble exhaust system?

Told you that a look at one would help
All custom with one silencer but two (very small) cats I think.

NoLimits said:

The flames will depend on air fuel and timing.

Like I said. I still think the default map's not going to cut it.

NoLimits said:

Shouldn't reduce life of you exhaust system at all.

Oh yes it will, believe me. All those bangs pack a fair bit of energy that pulses back up the pipe.

NoLimits said:

For those of you worried about getting caught without tunning with a cat ... tere are electric dump setups that can be opened and closed from insude the cockpitto allow exhauyst to vent to atmoshere or past the cat and back into the exhaust down-stream if you want.

That's not going to be an easy job to get a pair of them in I can tell you. No place to vent out either (there's a totally flat floor under almost all of the car).

Brian, get yourself in a Noble soon. Everything WILL be much clearer.

Cheers

Phil

[NoLimits]

ThatPhilBrettGuy said:

NoLimits said: What are the specs of stock exhaust inner and outer diameter from turbo back? How many cats/resonators? I am guessing two mufflers ... but of what size internally ad externally? Are will known brands used or this considered a custom Noble exhaust system? Told you that a look at one would help All custom with one silencer but two (very small) cats I think.

I am not flying into Ohio just to look at the exhaust. However, I agree, a visit is in order ... but I will not be going very soon.

The essential specs here are the inner diameter and flow of those components. Two cats, especially "very small", leave room for improvement ... even if they do flow well. Pipe inner diameter and routing is essential to efficient exhaust flow ... and turbo motors need a lot of flow ... atleast smooth bends with 3 inch inner diamtere for good efficiency ... as I am sure you comprehend. Corky Bell made a good book or more about this. So, the one muffler must just have those two pipes come out of it. I would think there may be two mufflers due to the dual pipes.

I have seen some detailed pics of the engine bay. Granted, I have not looked at all of the clearances and detail in person ... but from what I have seen I bet there is room to work with for custom setups. Not positive though ... but usually ... almost anything is possible ... especially the small mods that I mentioned.

ThatPhilBrettGuy said:

NoLimits said: The flames will depend on air fuel and timing. Like I said. I still think the default map's not going to cut it.

I was just agreeing and explaining that it is not only whether you're running rich ... but timing may be a factor too. Friendly discussion here.

ThatPhilBrettGuy said:

NoLimits said: Shouldn't reduce life of you exhaust system at all. Oh yes it will, believe me. All those bangs pack a fair bit of energy that pulses back up the pipe.

So, you're saying that you think backfire will damage the piping itself ... causing metal piping to deteriorate and break over time? What material is the metal on stock exhaust? In my experience, the most frail part of the exhaust system is the cat ... and as I said before "if you have no cat to replace .. then you have no cat to repalce". I mean, I suppose even water and air does erode over time ... but I have never considered a metal pipe having lifespan issues due to combustion of tolerable rates (the minimal amount of rich/timing condition to cause flames and pops while still allowing the motor to run almost unnoticably different). I would think that in order to break down the pipe ... the engine would have to have a big meltdown ... and even then the pipe may still be well intact. I have never considered any type of lifespan issues with metal exhaust pipe put to it's use ... except for rusting.

ThatPhilBrettGuy said:

NoLimits said: For those of you worried about getting caught without tunning with a cat ... tere are electric dump setups that can be opened and closed from insude the cockpitto allow exhauyst to vent to atmoshere or past the cat and back into the exhaust down-stream if you want. That's not going to be an easy job to get a pair of them in I can tell you. No place to vent out either (there's a totally flat floor under almost all of the car).

Many people just dump right under whatever is there. Granted, you need to considerwhat temps of heat you're venting in relation to were you are venting it to ... true ... but ... there is often a way to work with things to a reasonable extent. This setup could be used several ways. Also, it would not need to be vented like that all the time. You could run it open for short 10 second blasts or less if you wanted to. I was just showing what's available.

As I said before: "I have seen some detailed pics of the engine bay. Granted, I have not looked at all of the clearances and detail in person ... but from what I have seen I bet there is room to work with for custom setups. Not positive though ... but usually ... almost anything is possible ... especially the small mods that I mentioned."

ThatPhilBrettGuy said:

Brian, get yourself in a Noble soon. Everything WILL be much clearer. Cheers Phil

All I asked for was exhaust specs. "I am not flying into Ohio just to look at the exhaust. However, I agree, a visit is in order ... but I will not be going very soon."

I am not sure when I will decide to get a Noble. I am looking into several options right now. I keep on considering the Ultima .. but I think I like several things better about the Noble. If I get the chassis, I may not even use that engine. Doing some research and contemplation.

Friendly convo here. I enjoy the analytical chat. Let's just make sure that we stay friendly and don't "nit-pick" when we think it could cause a scuffle. My chatting is simply for sharing/learning/and discussing many marvels and wonders and ideas .. while enjoying the company and same from other like-minded enthusiasts all over the world.

Best regards,

Brian

[ThatPhilBrettGuy]

Sorry, I should have be move clear about the CAT's. Saying small I meen short as in there isn't much of it so it's very free following. The diameter is quite big. I remember someone stating that the HP gain from removing them would be low (around 3HP. It may have been YellowShed and they developed the engine so I'd go with that).

Regards

Phil

[NoLimits]

Gotcha.

Still curious if anyone actually knows inner diameter of the exhaust setup from turbo back, the type of bends and flow path and the flow for the entire system.

[ThatPhilBrettGuy]

NoLimits said:

Gotcha. Still curious if anyone actually knows inner diameter of the exhaust setup from turbo back, the type of bends and flow path and the flow for the entire system.

Dunno about the inner diameter but all the bends are very wide and smooth with no kinks. I don't think there's going to be much back pressure.