blue monster

I have a nice shiny Greddy TI-C dual exit exhaust sitting in my garage waiting to be fitted this weekend.

The question is whilst the exhaust is off, do I go decat at the same time? Does it make much of a difference when combined with a performance exhaust or am I better off saving the cash, fitting the exhaust & leaving the cat on?

My S has only just had an MOT so if I did go decat I would not need to swap it back until this time next year.

Thoughts?

tej

Makes Heel-toe'ing/rev matching a lot nicer imo. Wouldn't do it for any power gains though.

Adriank

I'd do it S2k's sound better decatted IMO and it should help make a dual exhaust less boomy. It made a big difference to the sound etc.. On mine.
Garage R should have in stock

gbduo

Does the decat give you flames out the exhaust on the over-run or do you have to modify the ECU to be more aggressive?

I sound like a chav/child but something appeals about having a exhaust that pops on the downshifts!

m1bjr

The only time I ever see that is a blown S2k.
You wont get it with any system on the stock engine.

I like that noise too, my R26 with a Blueflame did it.
And this 335 with a Bastuck does it , but only at low rpm lifts.

Don't see the point of catless it's just a PITA swapping it for MOT time.
There are no real gains to be had, and I tried it on oem and Invidia.

B B

A de-cat pipe is but loose change compared with the cost of an aftermarket exhaust system so you might as well fit one. You will need an attachment called a de-fouler. Somebody better informed than me will explain I'm sure.

In my experience with an NSK Silent:
1. It does make the throttle very slightly more responsive.
2. I did not notice any perfomance gain.
3. It makes the car sound like a proper classy sports car, a crisp rasp and deep
growl. Think Maserati or Ferrari rather than naff cowboy oik Chav Astra /
Suburu sound-a-like.
4. There is no boom or drone at any revs.

gt750boy

To each his own. Mine's de-catted, I like the sound and there is a bit of a burble on lift-off which I like very much. Plus, it does weigh quite a bit less and the exhaust does flow freer if you have other mods. IF you need to change it for an MOT it is a very quick job of all of five bolts.

I would say do it. The more people that have de-cats the sooner we can all have global warming and see the ack of this snow.

Adriank

My car used to pop flames at times (I have been told this by following mates) when i had the AEM fitted...

I also have an anti fouler you could buy off me (never used) if you need one for a measely sum.

gbduo

Ah fair enough, shame

blue monster

Why do you need any anti/de-fouler - what is this & what does it do?

I have been reading Garage R's thread on decat's and there is no mention of these on there, just reference to O2 sensors to prevent an engine light popping on