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Discussion Starter #1
Hey all,

On a whim, after reading posts by Ulf on his new Novitec exhaust system (and seeing his pics) and researching other crazy Japanses guys who have done up their 147's I have decided to take off the big main resonator under the car. It's a massive muffler in the middle of the car and since I have my car so low, it scrapes up against my driveway every single day (and now I don't scrape at all!).

I just got the car back. It cost me $40 (Australian read: peanuts) to take it off and replace it with a straight through pipe (took 1 hour). It's big and heavy so I also save some weight (whoot!).

Initial impression: Turn on the car and yes the idle is a little louder (I have a Sebring exhaust) but nothing major, no massive difference.. I could have handled even louder.

Test drive. Car is feeling great and the sound in the cabin with all windows up is there, but it's very subtle. I wouldn't call it cabin drone at all. Nothing major, really no huge difference at all. Just a little louder, perhaps only 10-20% louder inside and outside but the sound gets louder with load (ie: higher revs).

So, all in all a great little weight saving mod I think! I am tempted to take off the 2nd little resonator right next to the back box too. But perhaps a straight through muffler design would do the trick and geti it super loud... not that I want that at the moment. I'm pretty damn content with the sound now.

Stef, Reuven, cyas tonight. I'll let you guys hear it 1st hand and take the car for a spin too.
 

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Might be worth considering replacing the factory resonators with HOTDOG resonators.
Should prevent drone in the cabin, are fairly light weight, free flowing , compact, and I believe quite effective.
It was suggested I replace the supposedly damaged one on my Ibiza GTI with two samall ones. The fellow I talked too said that they would be as effective or more effective than the original resonator for less than 1/4 the price of an original.
Luckily the problem was due to a missing support bolt left out by the dealer when they replaced the rear one under warranty.
When I complained about the noise they said that they had checked over the system and the resonator was gone. rant
 

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<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:<hr /><font size="1" face="Verdana, Helvetica, sans-serif">Originally posted by Justin Fox:
<strong>Hey all,

On a whim, after reading posts by Ulf on his new Novitec exhaust system (and seeing his pics) and researching other crazy Japanses guys who have done up their 147's I have decided to take off the big main resonator under the car. It's a massive muffler in the middle of the car and since I have my car so low, it scrapes up against my driveway every single day (and now I don't scrape at all!).

I just got the car back. It cost me $40 (Australian read: peanuts) to take it off and replace it with a straight through pipe (took 1 hour). It's big and heavy so I also save some weight (whoot!).

Initial impression: Turn on the car and yes the idle is a little louder (I have a Sebring exhaust) but nothing major, no massive difference.. I could have handled even louder.

Test drive. Car is feeling great and the sound in the cabin with all windows up is there, but it's very subtle. I wouldn't call it cabin drone at all. Nothing major, really no huge difference at all. Just a little louder, perhaps only 10-20% louder inside and outside but the sound gets louder with load (ie: higher revs).

So, all in all a great little weight saving mod I think! I am tempted to take off the 2nd little resonator right next to the back box too. But perhaps a straight through muffler design would do the trick and geti it super loud... not that I want that at the moment. I'm pretty damn content with the sound now.

Stef, Reuven, cyas tonight. I'll let you guys hear it 1st hand and take the car for a spin too.</strong><hr /></blockquote><font size="1" face="Verdana, Helvetica, sans-serif">Justin,

Looking forward to it mate! Cya tonight!
 

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Discussion Starter #4
Hey guys. I have been out driving all day and I have a few things to report.

1: The extra sound is awesome! Addictive.

2: My selespeed gear shifts are a lot smoother! This is very strange. There's a massive difference. Any suggestions as to how and why?!

3: There's a ****load more power in 2nd and 3rd gears. I am absolutely amazed at the difference this has made to the car. Best mod so far in my opinion! That standard resonator must be so damn restrictive. I will get Stef and Reuven and whoever else rocks up to my place tonight (Adrian and Jay will be here too I think) to test the car and get them to write a review here too.
 

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<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:<hr /><font size="1" face="Verdana, Helvetica, sans-serif">Originally posted by Justin Fox:
<strong>Hey guys. I have been out driving all day and I have a few things to report.

1: The extra sound is awesome! Addictive.

2: My selespeed gear shifts are a lot smoother! This is very strange. There's a massive difference. Any suggestions as to how and why?!

3: There's a ****load more power in 2nd and 3rd gears. I am absolutely amazed at the difference this has made to the car. Best mod so far in my opinion! That standard resonator must be so damn restrictive. I will get Stef and Reuven and whoever else rocks up to my place tonight (Adrian and Jay will be here too I think) to test the car and get them to write a review here too.</strong><hr /></blockquote><font size="1" face="Verdana, Helvetica, sans-serif">Sounds Great Justin.

But you sure the sounds & feeling aren't purely physiological??

If not thats what I call real "BANK 4 YA BUCK!"

If I feel a diffrence tonight, First thing Friday/Saturday morning I know what I,ll be doing!!! :D :D :D wink
 
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Hey Justin,

If you're keen to get a lot more "nice" noises (read as : more distinct twin spark engine sound), try removing the resonator at the air intake itself. I know of a couple of 156's with the air box resonator removed and those cars soound awesome.... growl-y actually - almost boxer engine like. My air box resonator came loose a while back (the mechanic who installed my Novitec drop-in did not fit the resonator back properly) and I had a lot of fun for a few days listening to the engine roar sans resonator before I fitted it back properly.

And the best part... you can almost DIY it if you're a keen DIY guy. Not that hard to remove the air box resonator.

On replacing the mid-section resonator (I take it it's the mid section catalyc converter) with a bullet will inevitably move your torque and bhp curve up the power band which explains the "additional" power in 2nd and 3rd gear as well as in the higher rev regions. But the downside is that your lower end torque will be reduced. At least that's what a few of us here have experienced with similar mods! :)
 

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Discussion Starter #9
JL156. The 156 airbox is different to the 147. I have already removed the air intake resonator/intake pipe on the 147 and replaced it with an Autodelta carbon fibre cold air intake. I have noticed better throttle response but no more sound. Reuven has a K&N rampod in his car and wow, the sound from inside the car with windows up is great! I am considering getting a K&N but don't really want to waste my Autodelta cold air intake. Choices choices.
 

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<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:<hr /><font size="1" face="Verdana, Helvetica, sans-serif">Originally posted by Justin Fox:
<strong>JL156. The 156 airbox is different to the 147. I have already removed the air intake resonator/intake pipe on the 147 and replaced it with an Autodelta carbon fibre cold air intake. I have noticed better throttle response but no more sound. Reuven has a K&N rampod in his car and wow, the sound from inside the car with windows up is great! I am considering getting a K&N but don't really want to waste my Autodelta cold air intake. Choices choices.</strong><hr /></blockquote><font size="1" face="Verdana, Helvetica, sans-serif">I know after hearing my car tonight Justin it will be a hard to make some decesions, some how we have to configure the K&N pod with the Autodelta cold air intake im sure we can do it some how!
 

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really, the parts cd must be a little out then :confused:

or maybe the weight includes all its piping, and i assume you only removed the resonator itself. :)

glad you saw a nice difference wink

did you notice any change int he consumption, by any chance?
 

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Discussion Starter #14
That must be it Banflu. The muffler guys cut just the resonator off so with the extra piping it would have been heavier.

I have not niticed any difference in consumption or a loss in throttle response off the lights.
 
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So Banflu, how much does all the stuff I removed weigh? Three mufflers with all piping?
 

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Ulf - part number 46739669 includes the "big" muffler/resonator, and the small silencer, together with their piping which ends at the back of the car. this weight 9.5 kgs.

the back box (46739672) weighs 10kgs (9.975 actually)

so you have removed nearly 20kgs :cool:

these are the parts which i'm talking about:



do you know the weight of the new system?
 
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