Exhaust System with Full Decat Help !
 

Hi Everyone,

I've got an Newage MY03 WRX & I want to change the standard crappy exhaust to a Full Decat System.:)

What I want to know is whats involved regarding the sensors?

Is there just 1 in the 2nd cat underneath the car & 1 in the down pipe?

I assume the 1 in the down pipe is a LAMDA sensor & the one in the 2nd cat is a heat sensor?

1st off What do I do with them when I install the new system?

2nd, do I have to have an ecu remap or will the ecu adapt with the new exhaust?

Thanks

Adam

yes to the remap :thumb:

I might be remembering incorrectly, but I can only recall three sensors in the exhaust of my 03:

1. Lambda sensor in headers
2. EGT sensor in up-pipe (in the up-pipe cat)
3. Lambda sensor in the rear cat (i.e. mid section).

The rear lambda needs to still be connected, as you'll get a check engine light otherwise. You can have the parameters modified at remap time so that it doesn't throw the CEL, but you can't get rid of it completely.

The EGT sensor can be removed from the up-pipe (if you're fitting a decat up-pipe) and replaced with a resistor (search for "CEL fix").

The front lambda needs to remain.

Thanks for your help guys.

So when it comes to fitting time I will have to have it remapped at the same time or it won't run?

It will run, but it *may* produce problems such as overboosting, leading to knock, leading to engine failure ;) Some people's cars are OK with a fully decatted exhaust and others have problems.

If it was me, I'd get it remapped soon afterwards (and I wouldn't boot it until after the remap). A remap adds so much more power than just an exhaust anyway, it will transform your car.

Nice 1 thanks for your sound advice !

What would expect to see in bhp increase with the full decat & ecu remap done ?

I think mine is about 227bhp as standard.

around 270-280 bhp, More importantly a much much nicer drive

http://i166.photobucket.com/albums/u...st-diagram.gif

Surprised no-one posted this up for you fella :thumb:

Cheers Guys,

Yeh I expect I would be happy with that kind of increase in power :)

Thanks for the diagram by the way, makes it alot easier to see whats, what.

Best get some cash !