Anyone running a decatted Polo?

[PoloGTi_15]

Thinking of Decatting mine for when i go stage 1 to get some nice pops and bangs. however if i were to leave the stock cat would it ruin it?

[jimmedy]

Well, it's illegal.... so I assume you're talking about doing it yourself, because your tuner / mechanic shouldn't be doing it for you.

Stage 1 is designed to work with the OE DP / cat. Stage 2 on these is just a tweak to that file for people who run a bigger DP so it doesn't start throwing codes from confused air sensors. As in, Stage 1 + Test Pipes File = Stage 2.

The DP is adding any extra HP, the tune effectively doesn't change.

If you run decatted with stage 1, your engine could start throwing codes because the lack of restriction is unexpected.

Invest in a good DP with a sports cat, or just enjoy stage 1 as it is. Or come at it from the front and upgrade your intake; you'll hear more induction sound from doing that.

[JustCruisn]

You may need a special tune as the ecu will expect the post cat sensor(s) to give a certain value which won't happen, so it may lean it out or just throw a CEL.

[nomadx38]

Stage 1 runs on the stock DP fine. As said above stage 2 only really clears the CEL that's thrown from it.

There at are a few other changes that are made but not much. Boost can be increased if there was a previous restriction and timing etc can be adjusted to better suit the peak boost that comes on sooner.

Also there is the lean running issue that could effect you but if the 1.4 (or 1. is anything like the 1.2 I have it automatically trims the fuel injection anyway.

The pops, bangs and flames you get from catless though are a reason to do it in itself, especially starts on cold mornings haha

[bushman]

WTF, Why would you want pops and bangs! Makes you car sound faulty, and attracts cops.