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My SE came with a full 3 inch exhaust system when I bought it. It sounds great on a short blast through the hills but on a long highway run it has a booming drone to it that is headache inducing after a while, and I'm getting a few complaints from the passenger seat about it

For the time being I have pretty modest power goals on this car and will stick with the stock turbo, so I'm wondering if a down size to a 2.5 inch system might be a good idea to make it easier to live with on the road.

My questions are,

• Is fitting a 2.5 system likely to reduce the boom/drone/volume and would this be the best way to achieve this? If not what is?
• Is the 3 inch system just overkill on a stock turbo, or will there be detrimental side effects from down sizing like power limitation, spool time etc?
• If a 2.5 system is the way to go, is an off the shelf system like the Mania one worth going for, or should I just head down to the local exhaust shop?

PS.
I don't have the standard system to put back on or use as a basis for a new system.
Finding a new passenger is not an acceptable solution... so I'm told
The 3 inch system will not go to waste as I'm planning to start on a dedicated track car build later in the year.

Mate, you've gotta specify exactly what you have;
ie. cat, how long a resonator, what type of muffler?
From your description you've got a straight bit of 3" metal with nothing else!

I find a longer resonator gets rid of all the bad noises.

Like Bruce asked, what's under there already beyond just 3" piping? It would be far cheaper to install a new resonator and muffler to better control the sound, than replace the entire system. And if it didn't come with a CAT, it should and will make a difference.

3" is what you want for power though, it'll flow and spool better than a 2.5" system.

Also, if you use more RPM, you won't be able to hear the whining noise from the passenger seat ;)

Resonator or muffler change will help even with the 3 inch.
If it's drone I'd go a resonator. If it's generally too loud all the time then muffler or both.

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It's a nitro dann exhaust as per picture....

SS11 wrote: It's a nitro dann exhaust as per picture....

^^ What SS11 said!

Thanks Shane

Saves me a trip under the car to take some pics and measure up.

If it's one of Dann's, then just call him and ask his recommendations. I have one of his too, I don't find it drones, but for some it could be loud. Maybe a muffler is your best bet, or like speed suggests, do both res and muffler.

Oh, and if noise isn't your bag, don't do the intake!

No prob CR, trust the SE is treating you well ironically the other day I found one of the braces I removed when the exhaust went in, it was a very tight fit with the 3"... you are welcome to it, I can post it, or you can collect from Blackburn or emerald if u like (PM me if u like)

ManiacLachy wrote:If it's one of Dann's, then just call him and ask his recommendations.

I was thinking Dann would probably chip in here anyway. If he doesn't I'll give him a call.

ManiacLachy wrote:Maybe a muffler is your best bet, or like speed suggests, do both res and muffler.

I don't want to get into chopping and modifying a nicely made system too much, as I'll use it as is on another project if there's not a simpler solution.

Its only at certain RPM and loads that you notice the resonance. On the twisties where you're constantly changing engine speed and load, its not an issue and sounds pretty awesome.

Unfortunately it seems to hit right on highway cruising speeds.

ManiacLachy wrote:Oh, and if noise isn't your bag, don't do the intake!

Too late, it came with the intake done!

CrazyRacer wrote:I don't want to get into chopping and modifying a nicely made system too much, as I'll use it as is on another project if there's not a simpler solution.

Its only at certain RPM and loads that you notice the resonance. On the twisties where you're constantly changing engine speed and load, its not an issue and sounds pretty awesome.

I'm a bit surprised as Dann's systems are not known for drone. Have not been in one at highway speeds though.

You have yourself a great system there. Yes you could go to a 2.5 but it would cost.

How about sourcing a stock 2.25 SE system and bolt it on?

If you don't want the 3 inch, then sell it to me

Or earplugs for your passenger

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Dann built a 3" for me and it was noticeably quieter than a bog stock car.
I'm guessing it has to do with muffler choice?

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smy0003 wrote:Dann built a 3" for me and it was noticeably quieter than a bog stock car.
I'm guessing it has to do with muffler choice?

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Do you mean a stock NA8 or a stock SE?

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Ahhh yes, should've qualified that. Quieter than a stock NA8 or NB8B. Never had the pleasure of driving an SE unfortunately.

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Turbo cars can be quiter due to the exhaust flowing through the turbo housing.
I thought that yours was 3 inch then stepped down to 2.5
If so than that would make it quieter again

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Yes, turbos make great mufflers.
It only stepped down to 2.5 to clear the obstacles at the back of the car from memory

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