Rill

Just after some ideas before I make a final decision about the exhaust system on my 06 STi.

I appreciate the technical/performance differences between the two but it's noise levels I'm really interested in. I'm guessing a de-cat would be louder than a sports cat but how much difference is there likely to be between the two?

My main concern is the 102db noise level limit imposed at the track day that I'm booked onto later in the summer....my first one, can't wait!!!! I'd be gutted if I got turned away cos my new found "burble" was too much!

Anyone out there with a de-catted 06 STi who has had some noise readings done and would care to share the results?

Failing that, any opinions/advice would be much appreciated.

Thanks.

D1CCY

Now he gets worried.

A decat will be louder because even if a sports cat doesn't restrict flow it will still smooth out the pulses. Decatted cars I've heard have a much harsher bark and I suspect would get close to the noise limit. Last time at Elvington I was measured at 98.7 db without plug against the limit of 102 (03STi). This with prodrive sports cat and SC 3" middle (with resonator) and rear. You don't want to be forced to use a plug as this will undo any decat advantage. Personally I'd go the sports cat route as it is legal and doesn't cause bother at MOT time.

Are you going to Ketch tomorrow.

Cheers, Diccy.

Rill

But think of the POWERRRRRRRRRRRRRRRRRRRR!!!!!!!!!!!!!!!!!!!!!!!

Yeah, I'll probably be there at some point tomorrow night matey.

D1CCY

You might get a couple of headline bhp with a decat but in use I doubt you'd be able to tell the difference (apart from the noise). You know what mine goes like and that's only a 2.0 with a cat. When I had mine remapped Adam was mildly twisting my arm to decat but I wasn't comfortable with the idea and I already had the sports cat bolted to my car.

dynamix

iTrader: (3)

Mine is an 06 2.5 STi and I use a full Miltek Sport 3 inch decat system and it passes noises tests without problems at track days.

Sounds lovely too

IainCam

Do you have any sound clips you can put somewhre for us to hear?

It was the Miltek one I was interested in as well, looking for something that sounds nice without being too intrusive (had a 94 wagon with a full Magnex decat and it was a bit OTT on long runs).

pippyrips

same here

dynamix

iTrader: (3)

video clip here

www.bigpower.co.uk/~murano3/Dunk.wmv

put the sound up

we were trying to drift ... oops

D1CCY

I'll never persuade him not to now.

funkyspider

Keep ur toe in ya big girl - I saw u braking on that corner

Sounds lovely tho.

dynamix

iTrader: (3)

- I know I should have but there were big concrete pillars not far off the track and I couldnt bring myself to disconnect my brain

Sound is deep and meaningful but not intrusive at all off boost on cruise - on boost it is lush 8)

IainCam

Sounds nice without being too OTT... I'd work on that drifting though

Rill

OMG!

I think I've just done something very childish in my pants!

dynamix

iTrader: (3)

that was the first time I had tried - I got slightly better as the evening progressed but not much ... pmsl - still laughing about it now.

IainCam

I think Miltek do a sports cat as well though which shouldn't lose that much of the noise/bhp.

IainCam

I'm not saying I could do much better... would prefer somewhere with a bigger run off to practice though... esp with such a new car

dynamix

iTrader: (3)

the whole idea was to have a laugh - more run off would have been great but we were trying to drift around the two corners as one..... trying being the operative word lol.

it was a pretty much alien concept to me - trying to provoke oversteer and hold it there - I normally drive much smoother than that ... honest

back to the exhaust - yes, Miltek do a sports cat version but it is quiet expensive and seeing as MOT time isnt for a while I thought I would go without a cat and put one in before the test.

Great build quality on the exhaust and fit and it is not loud by comparison to some of the other exhausts on the market - in fact probably one of the quietest. But I just wanted that would work, sound good and release power. Boxes ticked for all of those for me

IainCam

What all have you done to the car, just the exhaust? I notice in your "My Scooby" it's "std"

dynamix

iTrader: (3)

hmmm - I really must update that profile

dynamix

iTrader: (3)

Whatever exhaust you decide to change to - a remap is a must at that time.

Without it, the car would seems extremely quick for about 10 minutes before....



the engine blows itself to bits through the overboosting.

D1CCY

Don't worry, he's booked into SC for remap inc fuel pump and exhaust. He just can't make his mind up between sports or decat. I'm taking the day off and joining him. Will be nice to go to the Clinic and not get my usual big bill for something ambitious.

dynamix

iTrader: (3)

good to hear - I know my engine would not have lasted very long at all.

It boosted to 1.6 bar in an instant even on half throttle on a sedate drive around before mapping commenced

in a way its a shame becasue that felt sooooo fast ... but it would have ended in tears.

Go for the decat version and exhaust wrap the downpipe too to help spool up times and underbonnet temps

Rill

And I can't wait.......

....only 15 more "sleeps" to go!

dynamix

iTrader: (3)

IainCam

<chuckle>