cat replacement pipe

[GIGOLO]

Has enyone used a straight through replacement pipe for their cat converter?

I am looking at getting one made up for track days and drags, but not sure whether to keep the Lambda sensor just behind the cat.

My thoughts are that, removing it will cause the car to run rich as it is missing a sensor and may try to run in a " safe " mode. Or if I leave it, it will cause the sensor to read worse pollution levels than if the cat was present and it may run lean.

I am currently runing a full 3" systems, PFC, FMIC, 550cc injectorsand T3/T4 turbo.

If anyone has used one let me know if you have had any ill effects, and any noticable performance gains/losses.

[Beer Baron]

the sensor in the cat is a cat temp sensor. the O2 sensor is in your dump pipe, well before the cat. no need to hook up the temp sensor, it just activates the warning light on the dash which is there to prevent you parking on long grass when your cat/front pipes are glowing red thus igniting the grass and burning your car to bits.

[PHATR32]

i always thought it was to tell you when your cat was overheating, so you can back off to avoid damage?

steve

[Sydneykid]

You can buy them off the shelf, no need for a custom one:cheers:

[R31Nismoid]

yep, not an o2 sensor.

I dont even have mine connected and ive done what your gonna do,

Just tuck it away somewhere or cable tie it up. No harm

[GIGOLO]

Thanks for your help guys,

I need to get a custom one because the car has the cat welded to the exhaust system, and I will need to get flange plates installed to bolt it on and off.

Any idea on the performance gains of doing this?

I know it depends on how effiecient your current cat is, but what has been your experiences?

[Beer Baron]

i always thought it was to tell you when your cat was overheating, so you can back off to avoid damage?

steve

no, it's to warn you of all that heat in your exhaust so you wont park in long grass and blow your car up or start a bush fire.

[Sydneykid]

Thanks for your help guys,

I need to get a custom one because the car has the cat welded to the exhaust system, and I will need to get flange plates installed to bolt it on and off.

Any idea on the performance gains of doing this?  

I know it depends on how effiecient your current cat is, but what has been your experiences?

Best I have seen was a 40rwkw gain. Least I have seen was a zero rwkw gain, that was with a Magic 4" cat. Pick a number:cheers:

[yogi000]

can you fit a magic 4" cat onto a 3inch system???

[nsm034]

You can buy them off the shelf, no need for a custom one:cheers:

do you know who sells them? are they cats a standard size or what ? thanks

[Beer Baron]

can you fit a magic 4" cat onto a 3inch system???

you sure can.

[FATGTS-R]

The magic cat manufacturers can supply 3 inch reducers if you want or you can get your local exhaust shop/yourself to do it.

They retail for $500.00 or $350 trade.

Search "magic cat" and look for sydneykids comparison with a magic cat, "highflow" cat and straight pipe. Interesting stuff.

[nsm034]

The magic cat manufacturers can supply 3 inch reducers if you want or you can get your local exhaust shop/yourself to do it.

They retail for $500.00 or $350 trade.

what a rip .$500 for a piece of pipe about 8 inches long

[MidnightGTR]

I was quoted $100 to get flanges put either side of my cat so I can swap it to a straight through one for track days as someone above mentioned. He said the flanges would be about $60 and whatever labour, they are a cheap workshop though but that should give you an idea on price.

[GIGOLO]

Anyone compared the Magic cat to the Catco 5" the BATMBL sells?

[Beer Baron]

now that would be an interesting comparrison.

[jnr32r]

so are all cats the same length?

what if you buy one off the shelf pipe and its longer/shorter than the cat ???

[lwells]

what a rip .$500 for a piece of pipe about 8 inches long

I think he was saying the 4" Magic Cat is $350 trade / $500 retail, not an empty piece of pipe.

LW.

[nsm034]

mines already got the flanges on both sides of the cat so i should be able to just get piece of 3" pipe made up with flanges on it n bolt it straight on is that right? i would need gaskets too right?

[GIGOLO]

Thats right. If you want to bolt it on and off easily get the steel gaskets and not the graphite gakets as they arn't so sticky after they have been used.