Technical Sei-Removing Cathalytic Converter

[AppleSei]

Wat wud u advise oldschool?

Do you reckon its a bit of grey area, expecially for this country???

 

[spike2002]

i have just been talking to my old man who is a qualified mechanic and he has said if you remove the cat the car will not pass mot so will not be road worthy. thats in uk but not sure about abroad

 

[Leroy]

Go to a good exhaust place, get them to make up a decat pipe..If the lambda sensor is in the same pipe as the cat, make sure the replacement pipe has a hole in it for the lambda sensor....

...That easy!

I thought that you dont need lambda sensor if you aint got cat ))

 

[Leroy]

I have a 2001 mpi sei and I have done the whole de-catting thing! I would highly recommend it for a great sound and extra power. The problem with the mpi sei's aka ones made after 10/2000 is that the cat converter is not under the car as on the earlier single point cars its in the exhaust manifold if you remove the manifold heat shield (which can be difficult) you can see this, so basically to de-cat you have to buy a sports manifold I have the supersprint 4-2-1 which is to my knowlege the only one which will fit and the best!!

The next problem is the lambda sensors my ecu warning light is permanently on (have thought of disconnecting the bulb but thought better!! Basically the mpi has a lambda sensor before and after the cat, you have to leave the one which goes in before the cat connected and put it in your new manifold (although the lambda sensor point needs moving on the supersprint as it was designed for an spi car (have I lost you yet!!) Had to have this done specially alternatively i hear there is a lambda extension available from janspeed (or so i am told). You disconnect the lamba after the original fiat cat altogether. This is the set up i have a hell of a lot of work but well worth it the car just pulls so much more now more torque especially.

Hope this helps (or doesn't confuse) lol

James

Damn right you lost me )) I thought you just get the dem cat out and that`s it ) So basiclly what you are trying to tell me is that without new manifold
thar is no way to get it out ?? Btw how much is it for new manifold ?? it is
impossible to get it here in czech. Because only old people buy Seis ))

 

[Leroy]

And leroy before a forget you say your car is chipped who did this for you and did it make much difference?? Cheers

Well I am very proud of this. I have got chip from very good company that tunes cars for years here in the Czech Republic. For 100 quid I have got 11 bhp up . I have got 5 years warranty plus I have got run on engine break ( I dont know if this is right word for it. I shows the power of your engine. I have seen charts
and believe it or not 11 bhp up + lower fuel conspumption by almost 1 litre. It
all took 20 minutes to upload new chip

 

[andy.littler]

have all sei sportings always come with a cat???
just wondering cause cut top off mine a put straight through pipe in it and then re-welded top back on looks part and passed mot

 

[AppleSei]

Most cars of our age should have them as standard!!! Even the odd uno might be lucky and get one

 

[Liam]

Well I am very proud of this. I have got chip from very good company that tunes cars for years here in the Czech Republic. For 100 quid I have got 11 bhp up . I have got 5 years warranty plus I have got run on engine break ( I dont know if this is right word for it. I shows the power of your engine. I have seen charts
and believe it or not 11 bhp up + lower fuel conspumption by almost 1 litre. It
all took 20 minutes to upload new chip

Th engine brake is called a "rolling road" over here or "dyno".

Did you get results before and after the chip?

I don't know where else you get 11hp for such a small amount of cash, thats great Leroy, well done!

Liam

 

[arseofbox]

I thought that you dont need lambda sensor if you aint got cat ))

Regardless of there being a CAT or not, there should be a Lambda sensor.

The ECU uses it to monitor the burning conditions and alter the fuelling as needed

 

[Leroy]

Th engine brake is called a "rolling road" over here or "dyno".

Did you get results before and after the chip?

I don't know where else you get 11hp for such a small amount of cash, thats great Leroy, well done!

Liam

Well here in Czech Republic everything is much cheaper then anywhere else for example front bumper (tuned) costs here around 40 quid it is laminated not ABS but anyways it is great price.
Btw I have seen the chart before chipping and after on the dyno and I was
amazed. I was worried that engines lifetime will be affected but I was assured by 5 year warranty )

 

[jamie86]

i have just been talking to my old man who is a qualified mechanic and he has said if you remove the cat the car will not pass mot so will not be road worthy. thats in uk but not sure about abroad

Sorry but he's wrong.. the majority of cars will not pass an emissions test but a well set up car will....

(I know of someone running a MK3 Astra with a 2.0ltr XE on TB's that passes it's MOT without a CAT... He also happens to be an MOT tester as well...)

 

[spike2002]

yeah you can get it to pass mot if you know the the operson who is passing it.

so how would i set my car up if i de cated it to pass mot ???

 

[jamie86]

it's not so easy on a cento but if it is a car running on a programable ECU then you can do anything... like the F1 engine that was mapped to play a tune...


It's not just because he's an examiner it's that his car runs v.well and efficiently....

Trust me as obviously he can't test his own car.

 

[Smiler121]

MPI Sei-Removing Catalytic Converter

Basically the mpi has a lambda sensor before and after the cat, you have to leave the one which goes in before the cat connected and put it in your new manifold (although the lambda sensor point needs moving on the supersprint as it was designed for an spi car (have I lost you yet!!) Had to have this done specially alternatively i hear there is a lambda extension available from janspeed (or so i am told).

You disconnect the lamba after the original fiat cat altogether.

I know that this is an old thread, but it throws up a question I don't think that I've spotted elsewhere...

I am planning to get a lambda point made up to go after the cat when I replace the Mpi manifold with a Supersprint & install the cat, this means that the disconnect altogether thing shouldn't be an issue for me.

Can anyone please tell me why the 1st lambda point would need moving on the Supersprint when used on an Mpi rather than an Spi?

 

[chaos]

Re: MPI Sei-Removing Catalytic Converter

Can anyone please tell me why the 1st lambda point would need moving on the Supersprint when used on an Mpi rather than an Spi?

Might be because the sensor mounting is in a different place on the SPi manifold to the MPi version, so the standard lambda sensor wiring won't reach the harness plug and the mounting.

 

[Smiler121]

Surely it would make more sense to extend the wiring to the Lambda than add another hole in the manifold though?

Mainly wondering 'cos I've been offered a brand new system which would be fully ready to assemble onto an Mpi without further welding required for £600 but I need to make sure I've not missed anything I need to specify before I pay up.

I know I'll need to get hold of bracket labelled 14 in the Spi Eper pic & the gaskets & bolts I'll need if they aren't supplied, but did not see why the Manifold should need modding.

 

[randomizered]

It shouldn;t need moving at all....got a picture of the manifold?

Kristian

 

[fingers99]

I think the first lambda position should be OK. It's the second one which will both need to be there and probably the wiring extended. Note that Rallycinq recommends the use of the special heat shrink with glue inside when mucking about with wiring on lambdas, otherwise you may encounter problems when you go through a big puddle!

 

[Smiler121]

It shouldn;t need moving at all....got a picture of the manifold?

Kristian

The reason I asked in the first place is that I did not think that it was necessary to move the 1st Lambda point, I'm glad you've confirmed what I thought by suggesting I shouldn't need to Kristian.

I haven't bought one yet, but have been offered the full system £600 prepared with Sportcat & 2nd Lambda boss to be ready to fit myself including delivery, & I'd not thought the Lambda point in the SS manifold needed interfering with.

I might delay getting the Spi setup now though (although it is something I'd like to do soon & I've just ordered the bracket that bolts to the exhaust near the cat). Originally I thought that the large hole just after the flexi pipe I had was causing a faulty reading due to complete loss of back pressure. I'd promised myself a whole new stainless system if I ever needed to replace any sections, but the big patch job of welding that my mate did seems to have held (cant feel/hear any leaks when I'm under the car now) & the faulty Lambda code is to be back.

The service schedule states to check the Lambda @ 27K & I'm on 28K so it sounds likely my mates diagnostics kit is right.