Just changed downpipe on MY01 WRX to a de-cat. Will get car remapped later this year but was wondering if it is still safe to drive the car hard before the remap? The other 2 CATS are still on the car and everything else is standard except K&N panel filter.

I read somewhere that due to reduced back pressure now that downpipe cat has gone that this can damage the turbo - is there any truth in this?

Thanks

PS - Pulls like a train now!!

 

I've been running my '98 STI IV without a Cat in the downpipe for 4 years. The rest of my system is standard. My biggest concern is that I get occaisonal backfires - which I know aren't good for turbos - mine had to be replaced at 50k miles due to a bit falling off one of the blades! Backfires can also lead to premature failures of the oxygen sensor at the top of the downpipe - I've had to have two fo these at £100 a go.

Other than that, I've had no problems - pulls like a train, & much better reving at the top end. I also get better fuel economy suprisingly!

 

Markyboy, I did the same on my MY02 WRX - had a full decat system in place (apart from uppipe) for about a year before getting the TEK3 done.

THe car experienced no problems, in fact it was only after the map that I realised it had been running slightly rougher beforehand (but nothing to worry about)

cheers
DaveR

 

Good Man DaveR, so I can stop driving it like Miss Daisy now then?

Just out of interest, what gave the biggest gain in performance the Decat or the TEK3?

Cheers

Mark

 

... yes I think so. Certainly no specialist I ever visited before getting TEK3 done seemed too concerned.

Although if I were you I WOULD consider if I were you installing both an uprated fuel pump and a knocklink before getting the remap. Someone else on here may be able to supply more detail on why but I believe an uprated fueld pump was a recommendation if you were running a decat downpipe, something to do with running lean otherwise.... ?

anyhow as mentioned I had no problems for a year or so with spirited on-road driving.

 

I think that the standard fuel pump is OK up to about 300bhp. A re-mapped WRX with just a decat should be fine without an uprated pump. But get an AFR meter fitted and then you'll know for sure.

Dave.

 

Safe = Affirmative! if you want to taste the fruit of your labors i do suggest having it tuned, then youll really love it!