Ricky 1982

Hi guys after treating myself to a header set and up pipe off eBay then found out that they are cheap s**t I sold it on and now looking at getting a up pipe de-cat fitted (by Japspeed) and it says in the advert that my car will not pass it's mot test??? Is this right even if the rear cat is still in place??? Please help I want one cheers

s70rjw

iTrader: (2)

Up pipe cat by itself will not get your car through MOT. The main cat is all you should need to pass with certainty, a well warmed up centre cat may get you through. Removing the up pipe cat will have little or no effect on the overall result.

matth76

If your rear cat is still in place or even your smaller rear (2nd) cat in place it will pass with a decatted up-pipe. Which year model do you have? In fact the hawkeye model (06-07) has a decatted up-pipe as standard and only the two rear cats. So in an answer yes you will pass MOT if you still have the rear cats in place.

Ricky 1982

Does anyone know if my car 2005 wrx 2.0 turbo has a 3 hole bolt up flange from the manifold to the up pipe or not as I'm trying to get one but this is the question I keep getting asked???

mrjelly

iTrader: (6)

For matth76
Are you sure about the hawkeye, I have been told by my mapper that the hawkeye has a cat in the downpipe, which is the major restricting factor and so have ended up buying a full system. Are you including this in 2 "rear" cats.
Does the standard exhaust not have a cat in centre section and in rear too?

matth76

Yes the hawkeye does have a cat in the downpipe (the biggest cat) and as you rightly say a big restricting factor. In total the hawkeye as standard only has two cats - one in the downpipe, and one in the "mid" or smaller centre pipe which connects to the downpipe, which is referred to as the 2nd smaller cat. Yes I was referring to these two cats as the 2 "rear" cats (I probably wasn't clear as I was pretty tired last night when I posted my reply ). There is no cat in the main centre pipe which connects to the backbox. And there is no cat in the up-pipe (pre-cat), just before the turbo inlet, which the earlier years do have.

In response to the OP he will not fail by having a decatted up-pipe (assuming he has a pre-06 cat which has the cat in the up-pipe), as long as he has at least one of the two other "rear" cats in place, ie the main cat in the downpipe, or even just the smaller 2nd cat.