Relocation of Cat Converter

[Multi]

On most of our rides, the Cat converter is fitted at the exhaust manifold/outlet thus creating bottleneck and alot of heat in the engine bay. Does it helps to relocate the Cat to the bottom and by doing this will free the bottleneck as well as the heat...??? What do you think guys? Thank you...

Edited October 6, 2005 by Multi

[Genie47]

This is what they call a cat-back exhaust system. Yes, there will be improvement.

[Yeobh]

Yes you can , but the chances of premature failure is very high. Cat operates at a very high temp of 0ver 200deg C and if placed at slighly above road level it will come into contact with rain water reuslting in thermal shorck and stress, hit by stones, etc. During very hot afternoon, high temp cat may ignite the dry grass, paper etc under the carriage

[Spade]

you want performance change the cat and a get a high-flow cat

[Genie47]

I know of someone whose car's cat caught a flying plastic bag. The smell was horrendous.

[Multi]

You have a point there. So, I'll just need to make a protective cover for it...

[Atlantis_boi]

I know of someone whose car's cat caught a flying plastic bag. The smell was horrendous

 

Yes I've seen b4 too. Concidently, I was @ the garage & the car was being jacked up. The mechanic was trying to scrap off the melted plastic bag which gt stuck & messed up the outside of the cat

[Yeobh]

Cat at this position will allow heat be transfered to floorboard when your car is travelling at slow speed or comes to halt which in turns will affect your aircon performance resulting in high FC

[Multi]

So, what's your advice? I'm trying ways to reduce the temp in the engine bay as well as bottlenect at the exhuast...

[Maded]

If i'm not wrong... relocating the cat will cause you troubles when you go for your annual inspection.... how about wrapping the thing up with the same insulating stuff as they use on exhaust manifolds?

[Elfenstar]

On most of our rides, the Cat converter is fitted at the exhaust manifold/outlet thus creating bottleneck and alot of heat in the engine bay. Does it helps to relocate the Cat to the bottom and by doing this will free the bottleneck as well as the heat...??? What do you think guys? Thank you...

 

Well all the car's i've driven and seen have the cat/s under the car. I've actually assumed that all cars come with the cat under the car, and what 90% of people mistake for the cat is actually the flexpipe thats there to reduce the stress on the the exh. manifold bolts.

 

My cats have been roughly around where the front seats mount to the floorpan. i don't see why you can't have them there. The only problem i see would be space as all my cars have the undercarriage designed to have the cat's in that position (and nowhere else as space wouldn't permit).

 

I have had no issues with in-car heat or plastic bags for that matter. I've upgraded my entire exhaust to a 3inch system and as such the entire exhaust sits both closer to the ground (mind you my car has been lowered quite a fair bit) and closer to the underside of the floorpan, and i've had no issues with it thus far.

 

Before you move it, would you be able to take a photo of the cat you're talking about, just in case it's just the flexpipe.

[Maded]

hmmm strange... my cat seems to be right after the exhaust manifold (2 sensors mount to it) and before the flex-pipe....

[Elfenstar]

It's definately possible...but i haven't seen any.

 

More of the newer cars seem to have mutiple cats (the JDM WRX has 2, the ADM WRX has 3) so i'm sure they need more places for the extra cats, but don't mistake the the O2 sensor (usually plugged into where the exhaust manifold converges together) for the exhaust gas temp sensor (which is usually plugged into the cat).

 

If its 2 sensors then i'm prolly wrong and its prolly the cat...

 

Edit: I don't think theres much of a limit on where the cat can be placed. Up to manufacturers discretion on how they've built the car.

Edited October 6, 2005 by Elfenstar

[Yeobh]

Sorry unable to provide a perfect solution. Wherever the location, if you feel the merits is more than go ahead.

[Yeobh]

Inspector will look for the real cat but they are not worry by the location. Dummy cat can be detected by just taking the emission readings at the exhaust tail-end and checking the temp before and after the cat.

[Yeobh]

The post cat lambda sensor is a lead burnt type to make sure the cat is functioning.

[Andrewkb]

Question is, does the inspector actually bother to check before and after cat temperature ? I know some even fail for having welding lines on exhaust system !

[Maded]

Yeap, had a feeling we're not really on the same page here... u tokking about fast cars!! Me driving slow 1.4

 

But you're right I think i only have 1...