2nd cat

[micka]

Micra sr's have 2 catalyst's if i am correct, what if i was to remove the 2nd cat and weld a pipe in its place, will it sound louder and increase the cars performance, im using a magnex back box? Is it worth doing?

cheers.

 

[pap29]

all pre-facelift k11's have 2 cats one in the mani and one in the middle of the system, better performance will be seen by removing the firstcat in the mani by either buying a janspeedd downpipe (£70 new) or finding yourself a second hand performance manifold would be best so that it gets rid of the cat and provides good rumbling flow while still being moted easy.
do you have a k&n or are your running the paper filter?

 

[micka]

what about removing the 2nd cat and leaving the 1st in the mani? im running k&n mate.

im waiting to purchase a 4-2-1 manifold, but until thats certain was thinking removing the 2nd cat to make it louder and faster and ok for mot?

Also does a 4-2-1 remove the 1st cat automatically, £70 where from?

 

[micka]

?

 

[micka]

so if i leave the standard manifold on and remove the second cat, will it make any difference?

Also does putting a janspeed manifold automatically removes the first cat doesnt it?

 

[Alexx117]

janspeed will remove the first cat, youre better off getting a "frankspeed" manifold still pass mot then... ive got a de-cat on mine for the 2nd cat and i dont really notice the performance

 

[micka]

are the frankspeed ones producing the same bhp as the janspeed?

so get a frankspeed and decat the 2nd cat for best performance then?

 

[Alexx117]

not sure how much bhp but the figures are improved im sure frank will be over this thread soon and will give some input as to his manifolds and you will be road legal too

 

[Low Rider]

A de-cat pipe on it's own with the standard manifold will make little performance difference and also will not make much sound difference. Most performance is gained from fitting a janspeed manifold but even with a 2nd cat, passing an mot emissons test is not guarunteed.

With a janspeed manifold a de-cat will make a difference but it's only noticeable once the car has been re-mapped. I notice a definate loss of top end power with a stock 2nd cat fitted, (not something of a problem now we have a 200cpi race cat fitted).

In summary what you are proposing isn't worth it at this stage for the desired results.