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R33-gtst Apex Exhaust Way Too Loud .. / Mod?

Torques
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Torques Mentor

Torques

Posted
Posted (edited)

Hi there from London..

Here's the situation:

I recently bought a Skyline R33-GTST with an Apex(i?) exhaust installed.

It's what they call a straight through system, with no middle muffler.

The problem is, it's way too loud and draws lots of attention (good and bad) and it has to go!

Besides I don't like the look of the gigantic rear muffler where one could put an arm in.

I quite like the original double exhaust look (rear muffler)

I was thinking:

Maybe I could take an original R33 muffler and exchange it with the Apex rear muffler.

It would take some welding (for an adapter to adjust the diameter) but that is no problem ..

Here's my question:

Has anybody ever made such a modification, that is removing the middle muffler but keeping the original rear one?

If 'YES' .. what type of noise level can I expect from such a modifaction?

Thanks for the input ... any thought on this is highly welcomed ..

Cheers,

Andrew

Edited by Torques
(OO)SKYLINE(OO) Grand Master

(OO)SKYLINE(OO)

Posted
Posted

Ok, in my situation,

I have got aftermarket 3" Down and Front pipes with a high flow cat and the Standard Factory cat back exhaust.

It flows great with the 3" pipes and high flow cat but with the stock cat back its OK, can be better so I would like to upgrade to a Nismo Weldina or Kakimoto style exhaust to get the flow.

Noise its about 88 db so pretty quiet.

Is that what you mean..?

(B1) MR_fanny Grand Master

(B1) MR_fanny

Posted
Posted

id get an exhaust place to stick something inbetween to reduce the noise. wacking a stocker on will kill your performance especially if you see how the piping goes, its like an "S" and its smaller in dimensions so your pretty much bottle necking it. The labour you pay or put into making it fit you may aswell put it towards putting a muffler/resonator with flanges so you can bol on and off when you go track..thats if your super hard core.

eeiko321 Experienced

eeiko321

Posted
Posted
If 'YES' .. what type of noise level can I expect from such a modifaction?

Thanks for the input ... any thought on this is highly welcomed ..

Cheers,

Andrew

well how long is a peice of string???....... it depends on what sort of muffler or "resonator" (is the middle "THING")

id say give it a few weeks and see......... because some aftermarket exhausts...inside the muffler contains a plastic bag than holds the material.......and when it melts after use...it can be a fraction louder..... but somtimes with new exhausts...its more barky when new...but when it fills up with carbon it can quiet down a little.

so give it a couple of weeks.....

then take it to an exhaust shop......they can cut/weld anything

as for your question......yes ive removed Cats, resonators etc on my exhausts.....

resonator is designed is a small muffler that helps reduce sound. its no big deal if you rid it.

Torques Mentor

Torques

Posted
  • Author
Posted

Hello to AU!

Thanks for the replies .. much appreciated!

:)

I have bought a used but original exhaust near London and the guy who sold it was very forthcoming and offered to install the thing right on his driveway

for a little extra $$$!

Within 60 minutes he had changed the APEX to the original and I owe him for his help.

I still have the APEX exhaust and will keep it for future use.

It's so nice driving with a more silent exhaust and I think the low end torque has much improved.

(Though I miss the bad exhaust roar a bit) ;)

As for top end power I can not report for anything different (I drove 500km only and mostly in denser traffic)

And since I'm completely new to the Skyline and the oil looks like it needs a change I have not pushed it at all.

(did not go over 4500 pm due to traffic and the car being new to me)

That's about it from my side :)

Cheers from London,

Andrew

Torques Mentor

Torques

Posted
  • Author
Posted
good to hear

does UK have Noise Pollution laws for motor Vehicles?

in aust, NSW its pretty strict...

Yes they have, not sure about the absolute levels:

http://www.direct.gov.uk/en/TravelAndTrans...ent/DG_10025601

I might settle for an exhaust with bearable noise levels but power potential.

Right now the car is stock as stock can be :D

http://www.strangelanding.com/skyline/lee.jpg

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