E60 550i De-Cat conversion and free flow

[Sooi]

Howzit people.

I got a Q................I removed the two cats from my 550i and the centre cilensers boxes to get a bit of a free flow.

Do I have to re map it or will it be fine?

I must say it sound great! Now you can hear it's a V8 :rollsmile:

 

[Turbo6]

Careful on sensors failing. If you removed the cats, rather replaced them with similar sized silencers and if there lamba sensors in the exhaust system after the cats, you may want to have them moved further back to compensate for it. The car will rev easier and freer but may loose torque, so suggest you contact a tuner to correct the map, cos the lambda sensor inputs will have to be adjusted or manipulated into thinking the cats are still there.

 

[Sooi]

Careful on sensors failing. If you removed the cats, rather replaced them with similar sized silencers and if there lamba sensors in the exhaust system after the cats, you may want to have them moved further back to compensate for it. The car will rev easier and freer but may loose torque, so suggest you contact a tuner to correct the map, cos the lambda sensor inputs will have to be adjusted or manipulated into thinking the cats are still there.

Thanks for the advice. I will look into it. I should have explained in more detail because what I have done was remove the sensor from each cat cilinder then cleared out all that white stuff inside and made sure it was super clean then replaced the sensors. I unbolted the exhuast from the cats to clean them out.

So basicly the empty cats are still inplace with the sensors they are just empty now.

I will defnatly look at correcting the map, you know anyone in the North West or even GP dont want to take changes?

 

[Twinz]

Remap/map/tune, what ever you want to call it, is essential :thumbs:

 

[moranor@axis]

before you tune you must take out the other cats because the gains you get from doing half is minimal compared to doing all...

 

[Sooi]

before you tune you must take out the other cats because the gains you get from doing half is minimal compared to doing all...

To take out the front cats would I need to replace the branches? I think the front cats are right in there.

The two cats I cleaned out was sitting just about behind the front wheels they were easy to clean out. I got a funny fealing the front one are not going to be so easy?:flyfun:

Where would be the best place to get it remapped?

 

[moranor@axis]

they dont look too bad just take the exhaust off and smak them with a stick...

you have done the others so you know how much work is involved... you could just take it to an exhaust shop for a decat its pretty cheap...

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actually it looks like you only have cats in the branches... it could be that they the ones you took out...

these are the other parts of the exhaust i see not cats:

 

[Sooi]

they dont look too bad just take the exhaust off and smak them with a stick...

you have done the others so you know how much work is involved... you could just take it to an exhaust shop for a decat its pretty cheap...

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actually it looks like you only have cats in the branches... it could be that they the ones you took out...

these are the other parts of the exhaust i see not cats:

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:joy:Thanks for the pics Moranor!! They just confirmed that my exhaust is cat free! Those were the same ones I knocked out, that just great!

Now just to do the remaping to get the best out of the V8 raise:

Is there anything else I can do for a bit more horses before I do the mapping like the air intake?

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Thanks to all the advise so far!! This site kick ass :bravo:

 

[Fordkoppie]

Another de muffler?? :fencelook: :biglol: