what are cat replacements?

[chris285]

i was just wondering what the difference between a cat, and a cat replacement is

is a cat replacement a pipe instead of the cat, and if so how does it reduce emissions?

 

[Saul]

cat replacement pipe is just that, a pipe to replace the cat and it doesnt reduce emissions at all.

you can however get high flow cats with a reduced number of cells per square inch meaning higher flow but retaining the emissions control

see http://www.millteksport.com//hiflow.sports.cats.cfm

 

[chris285]

damn i can't seem to find anywhere that sells em for my car a 1.4 1999 ibiza

just wondering if i would be cheaper than the cat which is costing me 300 or 400 quid atm

edit - looking at the price of the sports cat for a mk3, i doubt its any cheaper ah well

 

[Stu_HR]

A 99 Beeza must have a CAT fitted to pass the MOT.

Time to bite the bullet I'm afraid.

 

[chris285]

A 99 Beeza must have a CAT fitted to pass the MOT.

Time to bite the bullet I'm afraid.

so is it the newer model's that don't then or what?

i just don't get how it works thats all

edit - will just have to keep to car for longer then

 

[edc]

93 (?) on compulsory fitment of cats to all production cars

 

[chris285]

so if u get them it makes ur car illegal on emissions then basically?

if so why can u buy them?

 

[edc]

U need the cat to pass the emissions. Emissions test for cat cars is tougher and tougher still over last year's limits. Ppl decat or use race cat in the hope of freeing up some power.

 

[chris285]

excuse my stupidness, but dosen't that mean that the cars are then not going to pass the mot?

 

[Stu_HR]

You're entirely correct. Every time the MOT is due you have to swap the CAT back on the car. Most people just can't be doing with all the faff if they plan to keep the car beyond the next MOT.

 

[xJib]

All cars made since 93 have had a CAT fitted as standard by the manufactures. It seems the previous owner of your car removed the CAT to get it to go faster.

FYI http://auto.howstuffworks.com/catalytic-converter.htm

 

[chris285]

tbh there is no difference between this and my old 1.4 sxe imo performance wise

guy at the garage said they could have done it cause the cat was breaking down, and gases going back into the engine could have cause ignition problems. so they removed it

 

[Dave_R]

I paid around the £200 mark for my sports cat. Go to a company that do custom made exhausts, such as Pro-Speed (Cardiff), Longlife, etc... and price up a sports (high flow) cat. Probably be cheaper than £300

 

[willis2008]

hi anyone got any info on a cat replacement pipe for a 06 cupra 1.8t??cant seem to find one anywhere

 

[Dave_R]

hi anyone got any info on a cat replacement pipe for a 06 cupra 1.8t??cant seem to find one anywhere

Try the other Ibiza Sectiom (Mk 4)

With the 20vT lumps you better off getting a sports cat from either Miltek or Blueflame..... Because you have two lamda's before and after the cat the ecu throws a fuss when it see's the same readings at both. I Think anyway lol

 

[ste4232]

the law states you must pass MOT emmisions test, you dont legally need a cat if it passes

Mine used to fail emmisions before i fitted de-cat pipe.

I went to powerflow and they charged me £40 to make and fit a straight de-cat pipe. Noise increase was amazing and felt better to drive too!

As for passing MOT its worth having friends is all im going to say. If i got stopped on side of the road it would fail test, thats the only thing. BUT, the De-cat pipe could be removed and cat re-fitted for MOT if i could be arsed!

 

[Mckellar]

noise increase from a de-cat is ear ache!

raspy beyond belief.

Surely cant be good for the running of the car if the car is forcing more fuel and air through the system, would it not run rich?

 

[pooch]

the lamda probe should be able to accommodate for the reduction in back pressure, removing the cat will definitely improve performance.
All de-cat pipes are sold as race use only, as they effectively make your car illegal, not sure of the implications with your insurance, probably makes it invalid!!

 

[Mckellar]

VOSA do spot checks on emissions levels.

If you fail, you need to re-sit an MOT and go to VOSA H/Q to get it signed that you now have a valid CAT.

 

[ste4232]

There was a take-off for fitting the origional lamda probe added to de-cat pipe so i could still use it. I found the noise increase just added to the sound of the car, not ruined it. Was much deeper though and louder! Mine ran rich anyway as i had fuel pressure turned up to allow it to fuel fine top end of the rev range with the supercharger fitted, which ment it ran rich on tick over.