Decat and warning lights?

[HG182]

So I’m looking into buying a decat pipe to finally enable me to fit my Ktec ultra exhaust.

Just want to get a heads up as to if this will throw up any dash lights or cause issues that need other things to sort them?

Any advice much appreciated

 

[bloke]

Worst will be a light.

 

[imprezaworks]

Maybe a light and i noticed a flat spot until it was mapped.

 

[HG182]

Thanks for the replies chaps! Just need to find a friendly MOT tester somewhere for when the time is right!

Interesting to hear about a flat spot! May want to get some extra bits before a map!

 

[hipwell]

Thanks for the replies chaps! Just need to find a friendly MOT tester somewhere for when the time is right!

Interesting to hear about a flat spot! May want to get some extra bits before a map!

Never caused a flat spot in either my 182 or my 172, I just took it off in the end due to the horrific noise on the motorway.

I think flat spots are more an issue decatting a 197 or 200.

 

[imprezaworks]

Mine had one and you could see on the graph the difference

 

[RIC172]

Yeah my 172 cup had a dip in the torque curve after decatting too. You could feel it when driving too. It made it up for it at the top end though. Strangely the decat never threw a light either

 

[Greeny.]

Good for noise and not much else without other major mods to suit, I notice no usable difference on track with 421 cams, remap, ikr and matched inlets apart from less rasp and generally less noise. However they are cheap and easy to swap if you decide you didn’t like it, if you don’t want a dash light on a 182 leave the rear lambda unplugged and cable tied up somewhere so it reads clear air and plug up the rear lambda hole on the de-cat.

Examples:

Mark fish modded standard cat:


De-cat:

 

[HG182]

Good for noise and not much else without other major mods to suit, I notice no usable difference on track with 421 cams, remap, ikr and matched inlets apart from less rasp and generally less noise. However they are cheap and easy to swap if you decide you didn’t like it, if you don’t want a dash light on a 182 leave the rear lambda unplugged and cable tied up somewhere so it reads clear air and plug up the rear lambda hole on the de-cat.

Examples:

Mark fish modded standard cat:


De-cat:

Thank you very much for that info. My thoughts exactly regarding the cheap to swap out etc. Really useful stuff about the lambda aswell. Fingers crossed it arrives soon, can’t wait for some rasp!!!!

 

[JB21]

Dash light
decreased MPG
Fuel smell in the cabin
Raspy tinny sound
No power increase
MOT fail

 

[R3k1355]

Dash light comes with a 2500prm limiter as well doesn't it?

Not really something you can just ignore.

 

[imprezaworks]

My decatted ktec sounded spot on tbf.

 

[flebay]

So I’m looking into buying a decat pipe to finally enable me to fit my Ktec ultra exhaust.

Just want to get a heads up as to if this will throw up any dash lights or cause issues that need other things to sort them?

Any advice much appreciated

For what it's worth my insurance policy specifically mentions that, and I quote, "if required the vehicle must have a catalytic converter fitted (sports cat acceptable) or if de-catted be capable of passing the emissions test of an MOT test".

 

[JamesBryan]

Dash light comes with a 2500prm limiter as well doesn't it?

Not really something you can just ignore.

Ey? What limiter?

My EML is on, still got the standard limiter.

 

[leeds2592]

Dash light comes with a 2500prm limiter as well doesn't it?

Not really something you can just ignore.

Nope, no limiter problems with the light.

 

[R3k1355]

Fair enough, I thought the little heartbeat light always came with a limiter.

 

[hipwell]

Dash light
decreased MPG
Fuel smell in the cabin
Raspy tinny sound
No power increase
MOT fail

I'd agree with all the above apart from the mpg.

My mpg definatly improved on motorway runs with the decat fitted

 

[RIC172]

Mine felt quicker with a decat but only at the top end. Also felt more responsive

 

[HG182]

Thanks to everyone for the replies and advice. After giving it some thought I’ve opted to get a sports cat for the car. Hopefully it will still be raspy enough as I really do like the sound!

 

[JB21]

Thanks to everyone for the replies and advice. After giving it some thought I’ve opted to get a sports cat for the car. Hopefully it will still be raspy enough as I really do like the sound!

They already have a 200cel sports cat as standard, no point going 100cel for the money they cost. Get group n timing instead as this will give real gains.

 

[JamesBryan]

You'll never pass an MOT with a 100 cell cat anyway unless it's red hot.

 

[HG182]

They already have a 200cel sports cat as standard, no point going 100cel for the money they cost. Get group n timing instead as this will give real gains.

What does “group n” timing mean and entail? Not the most up on knowledge just yet I’m afraid!

 

[JamesBryan]

What does “group n” timing mean and entail? Not the most up on knowledge just yet I’m afraid!

It means getting the timing adjusted to a certain degree of advance/r****d to the same spec as the group n clio tarmac rally cars were set to.

It takes someone who knows these engines though, not your usual backstreet garage.

Some good power gains can be had.

 

[R3k1355]

Needs a remap too