decat pipe

[turbo017]

sorry know there is another thread on this topic i'm looking to decat my mk3 ibiza but just wondering what the performance is like is it better than a 100 cell cat on the car any help would be good its due in after i've done it for a apr stage 2 will it cause any problem ie lam sensor or maf or any other problems

 

[acidstrato]

it'll be less restrictive but not a great deal of performance difference between the two

also you need the post cat 02 sensor disabled as well as a friendly mot garage

 

[Forbez]

Would it not affect the back pressure?

 

[turbo017]

garage all good but i dont understand about the lam sensor what i would need to do with them as the decat pipe alloews for them to fit in

 

[acidstrato]

the lambda 02 sensor will need to be refitted (no problem) but the values it will receive will be out of the norm range so engine management will kick up a fuss

but a remap like revo stage 2 or custom code can ignore it so it wouldnt cause any problems

 

[Beaker™]

garage all good but i dont understand about the lam sensor what i would need to do with them as the decat pipe alloews for them to fit in

IIRC you'll get faults codes even if both sensors are in place as they will tell the ECU that your exhaust gasses have NOT been through a CAT. The only hope you may have is finding a remap that eliminates the use of the 2nd probe, to fool the ECU. (will have to ask APR)

TBH your better off getting a race CAT, more money i know but a deCAT will NOT get you through an MOT and its a right pig of a job to fit, so prepping for an MOT would be a pain in the arse. Not to mention the fact that you'll see similar gains with a race CAT as you will with a deCAT, just without the fault codes/engine light.

 

[godzuki]

garage all good but i dont understand about the lam sensor what i would need to do with them as the decat pipe alloews for them to fit in

What de-cat pipe are you thinking of using? and where can you get them?
Just curious as i want 1

 

[Beaker™]

I'd seriously read up on decats on here before getting one.

 

[godzuki]

I'd seriously read up on decats on here before getting one.

Yeah i have!
Its going onto a mk2 golf (AYP code) so no mot problems for me

 

[Beaker™]

Yeah i have!
Its going onto a mk2 golf (AYP code) so no mot problems for me

If your using the standard AYP engines ECU then you will have problems, because AYP is whats fitted in the Ibiza.

 

[gavthelad]

Yeah i have!
Its going onto a mk2 golf (AYP code) so no mot problems for me

are you saying because of the year of the car.......it doesnt need a cat.

 

[Beaker™]

are you saying because of the year of the car.......it doesnt need a cat.

No matter what car ist going in, unless you 'map' out the 2nd probe you'll end up fault codes/limp mode. But your right, you won't need a CAT for an MOT.

 

[godzuki]

are you saying because of the year of the car.......it doesnt need a cat.

Yeah! Breaker is right!

I understand about the 2nd lambda probe & will need a revo stge2 to stop any ecu problems (unless i go megasquirt)

I will run it with the cat to begin with though,then when i put the ko3s on and go for a remap i'd like to junk it

I had heard of moving the 2nd probe further out of the way to fool the sniffer sensing less of the emissions,but i'm not sure about this as the gasses would be under pressure & it could be a myth (twas on an american site iirc) & i'm no expert.

 

[acidstrato]

if its going into a mk2 golf then you'll likely be having a custom downpipe made...so just stick a race cat on that and job done

 

[godzuki]

if its going into a mk2 golf then you'll likely be having a custom downpipe made...so just stick a race cat on that and job done

Well i'm pretty confident the ibiza DP will fit straight in qpeng do a pipe for them for £200 but theres a 2 month waiting list for them plus the cost of a race cat

Mind you, i hadn't thought of a race cat so mabe its something i should look into as it would solve a few problems and denote the need for a stage 2 which is not exactly cheap,so cheer's for the input

 

[acidstrato]

hmmm interesting

would never have thought the stock part would fit myself but its possible

 

[godzuki]

Yeah i know what you mean,however i think it fits straight in a mk2 ibiza which is basicly the same as a mk2 golf,i'm also gonna slot it in using the std subframe (mk3 golf) too so its gonna be a propper "parts bin" special lol!
Sorry for going off topic

Am i right in thinking lambda's work by sending "X" volts back to th ECU? if so could this be intersepted so to speak mabe using a resistor to give the correct number the ecu requires? i'm not good with electronics but it could be a starting point if someone were wanting to look into it

 

[acidstrato]

ibiza is a polo mate not golf

 

[godzuki]

ibiza is a polo mate not golf

IS IT! Hummmm
Mabe run into more problems then
hence the polo dash on the mk2 & the polo rear axle on the mk3
Still,i'm gonna be finding out the hard way pretty soon i still think it'll fit but mabe i shouldn't hold my breath lol

 

[cupra1.8t]

ive got a decat no problems wot so ever but have got revo stage 2 to block it out ! makes a lot better difference on mine.