djandyg

iTrader: (2)

Hey guys, I am adding a centre decat to my cat back set up tomo. I wil still have the up pipe cat and downpipe cat in place.

Some people have said I wont get a MIL light for the centre decat but others said i may - any thoughts? If i do, is the somewhere i can buy a mil eliminator?

Kedlestone

iTrader: (9)

When you say ''centre decat'' do you mean silencer fella? Your have no problems with dash lights, I've got a decat up pipe, decated 3rd cat and a straight through mid section. Removing the down pipe and replacing it with a decat will however throw up warnings.

djandyg

iTrader: (2)

This section in red mate, its the centre cat (1 out of 3) I already have a non resonated centre and a backbox.



Is yours remapped or running a PPP ecu?

daz1968

iTrader: (13)

I had no issues when replacing that pipe on my 03wrx. Never gave a cel. The ppp map doesn't disable any cels as I compared the two before I eventually flashed it to my car after fitting the other parts, but I ran with STD map and centre decat for a few months before fitting anything else. In fact the genuine prodrive pipe moves the sensor out of main gas flow to prevent cat on fire cel but not sure about after Market ones.

Midlife......

iTrader: (2)

Removing that cat from a newage will throw up a P0420 (cat below efficiency) CEL.......electronic fixes are pretty unreliable and the best way is to get the car re-mapped. Enginemapper charges about £225 I think, but there are other mappers

Think about panel filter and fuel pump if remapping.....

Cheers

Shaun

djandyg

iTrader: (2)

Thanks for the reply daz. I personally wasnt under the impression that i should expect a CEL as long as the other cats were all still in place and operating correctly.
Same goes with regards to needing a remap to safely run the pipe....as i cant see how it will particularly affect the spool time etc due it it being after the up and down pipes with them still in place and fully catted. Few others on another forum have advised it could cause boost issues....altho most people on scoobynet have said it will be fine as long as im not making and downpipe or up pipe changes....

djandyg

iTrader: (2)

hmm i guess ill have to see. Dont really want a remap at the moment due to insurance, was just after a touch more noise - not really interested in upping the power too much.

djandyg

iTrader: (2)

Iv just been out and had a look under the car and the positioning of the 02 sensor, and despite being mounted in that centre cat, is actually positioned just before that cat - therefore it surely must be there to purely monitor the gases after the downpipe only....otherwise it would be after the centre cat....?

This is on a blobeye WRX (03) btw...

daz1968

iTrader: (13)

On the prodrive pipe it still has the heatshields in place and the sensor is in a tube holding it out of the main exhaust flow so it don't pick up and increase in egt as far as I know it is just a cat on fire sensor not a lambda think the p0420 cel is when the downpipe is decatted. The STD ppp map defo has not got it disabled. When I did mine it didn't really make it louder tbh. I just fitted all ppp parts and then flashed the ecu with a ppp map I got off someone else. All the parts together made a difference but nit much on their own. Never had any probes at all

Midlife......

iTrader: (2)

The rear 02 sensor only measures the efficiency of the first 2 cats, even then the small pre-cat in the up-pipe doesn't do a big job LOL

If you just want a bit more noise then change the back box

Shaun

djandyg

iTrader: (2)

yeh that what i thought.....were talking about the 3rd cat tho with regards to your previous post lol.

Iv changed my backbox, and have a non resonated middle pipe already....this just seemed the next logical bit to buy without needing a remap. Only cost me £59 delievered from cobra so not gonna be too upset if it doesnt make much difference sound wise

Midlife......

iTrader: (2)

http://www.wrxtuners.com/forums/atta...st-diagram.gif

ah, I see you want to get rid of the 3rd cat in the midpipe..........no problem then

Shaun

djandyg

iTrader: (2)

you got it

any thoughts on the safety side of it without a remap? Again personally i cant see it majorly affecting anything boost wise to worry about...

Midlife......

iTrader: (2)

No mapping problems on the WRX / TD04 turbo. The TD04 turbo doesn't flow enough air to cause overboost issues and the DENSO ECU is clever enough to alter fuelling etc if the airflow through the engine changes.

Power will remain unchanged, turbo might spool a tiny bit earlier but the noise will change

Shaun

Kedlestone

iTrader: (9)

As above, no problem removing 3rd cat. Mine has been done with no issues.