Noise - and the lack thereof...!

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TimR

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Im sure this has been asked to death but as newbies (like me) are always joining the fold, I seek some input on what is possibly quite a subjective issue...!
I have recently fitted an X-pipe to my 4200. It goes better but I still havent touched the sides regarding noise...Its SOOOO quiet as to be rude IMO !
What works ? I want more noise .
My back boxes are in poor condition already.
Im desperate to avoid earsplitting decibels. I dont need cabin drone....I aint spending Larini money !
Tall order..?
What options exist folks..?

Grtzz...:cool:
 
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TimR

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Thannks- I have read that thread & Ive been warned a couple times that its fookin' loud ! But people have very different perceptions I reckon..?
Are there any sound clips uploaded on the forum atall..?

edit- found them...thats a bit earsplittitng tbh !
No happy mediums...?
 
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FIFTY

FIFTY

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I would do the cat section and keep the boxes standard - in fact that is what I have done! It is quiet at low revs then gets much louder 3500rpm and up.

I do have a pair of GS rear boxes to fit and a valve control kit, currently have zero drone - once fitted I expect to get low end drone with the valves open but hoping not with the valves closed at motorway cruising speed

Mine currently sounds like:

It doesn't distort the mic on the phone unlike Matt's old black GranSport lol
 
CatmanV2

CatmanV2

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I don't recall it being *that* loud. Pretty sure my GT with the h-pipe was louder.... :D

C
 
FIFTY

FIFTY

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TimR said:
That presumably requires a lower count cat to replace factory sections...?

Grtzzz....!
Click to expand...

Correct, if you go down the custom route you can get cat sections made for around £1k - go to someone reputable!

You can delete the primary cat and only have 1 pair (asssuming your car is Euro spec without the cats in the manifold) Do not install anything than a lower count than 200 cell which is what Larini use... mine has 2x 100 cell and it only just passes the MOT with a full cat test - I get an occasional CEL so I might get them cut out and replaced for 2x 200 cell or get Larini/Fabspeed as I did not use someone reputable :/
 
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TimR

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FernandoIsFasterThanYou said:
Correct, if you go down the custom route you can get cat sections made for around £1k - go to someone reputable!

You can delete the primary cat and only have 1 pair (asssuming your car is Euro spec without the cats in the manifold)
Click to expand...
Interesting point. My car is a RHD. I assumed it would be eurospec too but looking at the parts fiche- it has manifold cats as per USA & CDN !
How common is it to find this on a European car I wonder....?

Edit- so I’m convinced the exhaust tone and loudness is directly affected to the detriment of pretty much everything...performance included...
The conclusion of this is to consider removing the “ secondary” cats altogether...? Don’t want to change the h.eaders as theECU will flip out without O2 sensor data stream...( the section of exhaust are not interchangeable either so means a complete replacement I guess).
I’m thinking theLarinii race pipes, even though they say “ not for highway use” etc...
Can I get a car with only manifold cats through an MOT in the UK does anyone know....?

Grtzzzzz......
 
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FIFTY

FIFTY

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The majority of the facelift 4200/GS/Spyder post '05 were US spec with the odd exception on the early cars where they might have had ex stock to use or an ex keeper swapped them out. You can usually spot it by either seeing the cats on the manifold or counting the bolts on the manifold to cat section flange which are just visible by looking under the front splitter. If you have two bolts visible then it is Euro and if 1 bolt is visible then its US spec... downside of the Euro spec cars is that the ceramic cats fail after 40-60k.

None of that answers your question though, I have a MY2003 but I'm sure one of the ASBO club members will chime in shortly
 
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TimR

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Bumpity bump....!

CAN YOU GET A FACELIFT 4200 THRU' AN MOT (UK) WITH THE SECONDARY CATS REMOVED ?
( ie - manifold cats incl O2 sensors, race pipes/no 2nd cats, X-pipe and standard boxes)

Grtzzz....!
 
Evo Cymru

Evo Cymru

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Morning,

Not sure about your question but I have the US headers on my Gransport (2006) and was thinking about leaving the secondary cats and gutting the primaries instead (Craig Waterman did a vid on You Tube on how to do this with them in situ). Was then going to use some O2 'cheater' things so that the sensors would still be reading it as clean and hence not need to mess about with remapping etc. I doubt the MOT tester would notice and should pass emissions - err hopefully!

Olly
 
T

TimR

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Evo Cymru said:
Morning,

Not sure about your question but I have the US headers on my Gransport (2006) and was thinking about leaving the secondary cats and gutting the primaries instead (Craig Waterman did a vid on You Tube on how to do this with them in situ). Was then going to use some O2 'cheater' things so that the sensors would still be reading it as clean and hence not need to mess about with remapping etc. I doubt the MOT tester would notice and should pass emissions - err hopefully!

Olly
Click to expand...
Not sure you'd pass the legal testing (MOT here in the UK) Olly...
They stick a probe up the pipe during the assessment. Maybe Im wrong, if Fernandoisfaster can get away with it- perhaps I have my answer !!?

I'll have a hunt for the clip though...

Grtzzz....
 
jayblue

jayblue

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TimR said:
Bumpity bump....!

CAN YOU GET A FACELIFT 4200 THRU' AN MOT (UK) WITH THE SECONDARY CATS REMOVED ?
( ie - manifold cats incl O2 sensors, race pipes/no 2nd cats, X-pipe and standard boxes)

Grtzzz....!
Click to expand...

My GS marginally fails its MOT with secondary cat delete and two bolt US spec manifolds. Eventually got fed up paying my Indy £200 to reinstall the secondary cats for the MOT then remove them again immediately afterwards! I have considered gutting the cats in the manifolds and installing sports cats further back - apparently the lambda wires are long enough to be relocated so no eml problems but I don't know what would happen if an MOT tester noticed the primaries were gone?

The sound increase from a secondary decat is not as great as I expected but the throttle response is much crisper, there is more power and the pops and crackles are more pronounced.
 
Evo Cymru

Evo Cymru

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688
TimR said:
Not sure you'd pass the legal testing (MOT here in the UK) Olly...
They stick a probe up the pipe during the assessment. Maybe Im wrong, if Fernandoisfaster can get away with it- perhaps I have my answer !!?

I'll have a hunt for the clip though...

Grtzzz....
Click to expand...

True - will discuss with my friendly local tester when I take it up next time - not sure how close it is to the limit it is a present and how much margin I would have to play with. Will try and remember to post on here my results....
 
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