hi, right i have an 53plate wrx sportswagon with a sti back box. I am toying with the idea of putting a decating my second cat.

I don't know what would happen with my lambda sensor, will it have problems with engine management . Will the be any noticeable difference in performance and sound.

Thanks jon

 

If you mean replacing your downpipe then the new pipe should have a boss welded in the same place as the original and the lambda sensor should fit there.

At least this is the case with a classic. I'm assuming the later cars are the same.

 

yep newage decat pipe i fitted is the same.
best to have a remap if decatting due to increased flow and boost,also rear lambda can throw up a cel light this can be switched off when mapped