Annoying exhaust note...

[Stifla]

Hi all,

Well im glad to say im back where i belong...back in the vauxhall shed

Ive just got hold of a mk3 gsi and although its obviously been played with, in dire need of tidying up and a good service, doesnt seem too bad lol.

Thing is, its got this really annoying sound from the exhaust that i hear a lot of vauxhalls of this era making, its like a resonating tinny rattle at around the 3000rpm mark and it drives me up the wall.
It looks like a standard backbox with the two square exits.
They have ends that are turned inwards, does anyone know if this causes the noise?

Im sure this has been asked before but i couldnt find anything in the forum search.

Any help would be appreciated

[LEE69]

Its the design of the manifold,i have a magnex on mine and it got rid of it.

[Stifla]

Its the design of the manifold,i have a magnex on mine and it got rid of it.

Thats strange, because last year i put a redtop in a mk1 with the standard manifold and a homemade system and it didnt make this noise, thats what led me to believe it was the backbox!

[astragaz]

i know the noise your talking about, my mate had a astra gsi with the originall backbox and it made the same noise,

he swapped the backbox for another stainless one and the noise went

[DaveC_]

My XE calibra used to do it , was a fooked backbox.

Replaced it with a cheap and nasty rage one , what a mistake that was lmao

[PeteCup]

I had this on my GSI too, swapped the manifold for an SBD one and all it did was move the rasp/rattle up the rev range a litttle

Nex step was going to be welding braces accross the tubes of the manifold to strengthen it all and decrease vibration, but sold the car before that

Good luck.

[Dai G]

my xe calibra does it.its got a rattle in the centre box toowwwwaaaaaaaaaaarrpplmao

[Jack]

My mk3 Astra had a resonating sound at 3000rpm, and it spat fuel out and the mid-box rattled at idle.

Was such a cool car. Some of the baffles were loose in the mid-box, and that cured my humming noise too. Must have been the material the old one was made out of.

[Add_Gee]

my xe cally was the same, replaced the whole exhaust apart from manifold, and it still rasped.

[bigtomcat]

i think its just the standard noise theses cars make with standard system

both my astras do it so do 2 of my mates callys (we still have standard exhaust systems)

tbh i quite like that noise just to be differant lmao

nar i do dont ask me why mybe just got used to it

[DaveB]

It is the manifold. SBD type-A on mine made it go away

[turbo_nik]

Its just the standard "valver" rasp.Usually heard comig from novas and corsas.

My mk3 gsi made the same noise................till i removed the engine to make way for a v6.

[Krowlands]

not your cat shield then? Mine had a rattle at a given rev range (8v), and it was a combination of the cat undershield, the wrong exhaust rubber hangers (holding the pipe too close to the car, thereby hitting the shield), and the internal baffles in the back box collapsing.

Changed the backbox and rubbers, and it's as quiet as you like now..

[BlackIce]

My GTE used to rasp when I first got it - had a straight thru Scorpion system with no middle boxes, so I added one, and it still rasped. The only way I've managed to stop it is by putting a completely standard exhaust system on.

Loads of people suggested an uprated manifold would cure it

[PeteCup]

I tried all of the above...

Complete standard system without CAT
Standard system with CAT
Removed Heatshields
Fitted SBD manifold
Fitted complete scorpion system with CAT
Scorpion System without CAT

But none of the above cured it

I think its going to be very hit and miss as to wether you cure it or not.

[Corsa_shep]

throttle bodies...

i know the noise u mean, it makes the car sound like a pissy 1.4 or something, i hate the noise, all cav gsi's and astras make it,

[daveb948576]

your car sounds to me as if its had the inners smashed out of the cat.