Exhaust problem...?what cause

[alex_123_fra]

Hi all,

Don't know if I've jinxed myself with all the recent exhaust talk that's been going on. Took the car out today around 2pm-ish for a quick blat and noticed that after 10 mins of driving post warm-up, the exhaust made a very loud sound when going on full throttle.

The only way I can describe is like....the Panoz GT-R 1 sound off PGR3 on xbox360. It really was LOUD and the character of the exhaust note changed completely to almost a V8-like sound. Much as I like the change in exhaust note, I turned straight back and headed home. There was absolutely no change in boost pressure, temperatures and the performance was as ferocious as ever. When I got home I had a look and could find no exhaust holes/leaks and the exhaust bracket was intact (which it has been since October after Gary's fix).

Is it my baffle? Gary said it might be on its way out last year. Not sure what else it might be...anybody have any ideas? I won't drive the car until able to get it to a service centre. The Roush system may well be going on sooner than I anticipated

[Bugs M400]

Alex,
Mine made a similarly spectacular noise when the downpipe parted company with the rear turbo flange. It's actually quite hard to see the joint, but I suspect you would have heard it even at idle if that was the problem. Mine was fixed with a simple weld, although the whole lot had to come out to do it. If it's nothing obvious, I'd guess you're right with the baffle theory.
D.

[AMG Merc]

Alex, I think when the baffle comes away from its mounting inside the box the result is a lot od rattling. The other area for a blow (although past the box so not too noisy) is the pipe exiting the baffle side-plate at the weld seam - cracks here can be hard to see.

[robp]

Alex - could be that it's just the turbo to downpipe nuts have worked loose. There are 5 for each turbo and they are a b**** to get to but there are a couple on the rear turbo that you could try. If they're solid then probably the others are as well, but if not- there's your problem. Before fitting my Roush exhaust mine were always working loose. Makes the car much noisier under acceleration, although I could also detect the ashmatic note on idle.

[obes]

yep, something's loose somewhere mate

Looks like you'll just have to have a good hunt round. If you know anyone with a ramp or a pit, life is much easier if you can get the undertray off and look up at it.
(although getting the tray off can be a fair old challenge in itself!!)
I used some locking nuts that are very similar to these (the one's I used were from turbo technics as they're only down the road from me . Haven't had anything come loose since.

[AMG Merc]

Owen, you've given me an idea for a "You Must be Nuts" Emoticon now...

... then again I suppose it could also be taken to mean "Its The Nuts (dog's danglies) Mate"

Edited by AMG Merc on Monday 2nd April 15:51

[worty]

AMG Merc said:

Owen, you've given me an idea for a "You Must be Nuts" Emoticon now...

... then again I suppose it could also be taken to mean "Its The Nuts (dog's danglies) Mate"

Edited by AMG Merc on Monday 2nd April 15:51

We could have guessed that your nuts would be well polished
worty

Edited by worty on Monday 2nd April 15:56

[robp]

obes said:

I used some locking nuts that are very similar to these (the one's I used were from turbo technics as they're only down the road from me . Haven't had anything come loose since.

Hmm..I paid £7 per nut for silver-plated K-nuts as used on Ford WRCs. So who's the nut I hear you ask...
Best solution was to remove the gasket between turbo and downpipe as, according to those in the know, it somehow acted as a lubricant (!?) Don't ask me. Maybe I just had MUG tatooed across my forehead.
Whatever, I now no longer have the issue of self-opening nuts which use to occur at just about every track day when the turbos got a little warm..

[AMG Merc]

robp said:

I paid £7 per nut for silver-plated K-nuts

[alex s]

AMG Merc said:

robp said:

I paid £7 per nut for silver-plated K-nuts

Bit cheaper here...well a lot cheaper..thats a first, demon tweeks being cheaper than elsewhere...and these are the same silver plated ones..

www.demon-tweeks.co.uk/products/ProductDetail.asp?cls=MSPORT&pcode=GODH41-4

Edited by alex s on Tuesday 3rd April 00:24

[robp]

AMG Merc said:

robp said:

I paid £7 per nut for silver-plated K-nuts

No - more like
That's £70 for 10 replacement nuts. But they were silver plated...(guv)

[alex_123_fra]

Thanks for the ideas and suggestions everyone...very helpful. Regardless of what the problem might be, it sounds as though I may well be going for new nuts while I'm at it. Would prevent the current ones coming loose in the future if they haven't already.

Dammit...why couldn't the car sound this good when running normally

Edited by alex_123_fra on Monday 2nd April 20:20

[joolski]

AMG Merc said:

robp said:

I paid £7 per nut for silver-plated K-nuts

I wonder who woul have the balls to sell a nut for seven pounds a shot.....

--Jools

[robp]

joolski said:

AMG Merc said:

robp said:

I paid £7 per nut for silver-plated K-nuts

I wonder who woul have the balls to sell a nut for seven pounds a shot.....

--Jools

Ford WRC - just a pass through cost. They are genuinely silver plated, though, so I'm not expecting too many vampires to be messing with my turbos. Must be worth it.

[AMG Merc]

robp said:

so I'm not expecting too many vampires to be messing with my turbos. Must be worth it.

Thought that was Wolf's Bane?!

[robp]

AMG Merc said:

robp said:

so I'm not expecting too many vampires to be messing with my turbos. Must be worth it.

Thought that was Wolf's Bane?!

For those (like me) that did'nt know - "Lone Wolf learns that the evil god Naar has created an evil doppelganger of himself, the champion of the forces of good on Magnamund. A cat and mouse game between the two warriors ensues.."
Sounds about right for one or two of the recent threads..!