Exhaust packing

[Steve_D]

Has to be done as the beast is getting too loud.

What material should I be looking for and best source?

Not keen on going with loft insulation as the general comments I have heard all agree that it blows out almost as fast as you can stuff it in.

Many thanks
Steve

[Pb3]

Im going for a special kiln insulation material next time around. Reports suggest that it never burns away I can't find a link as yet, I will check at work tomorrow.

[Steve_D]

Pb3 said:

Im going for a special kiln insulation material next time around. Reports suggest that it never burns away I can't find a link as yet, I will check at work tomorrow.

Went looking for that and found reference to it being a class 2 carcinogen so will give that a miss.

Have ordered SS wool to wrap around the pipe and back that with the Basalt wool.

Steve

[Pb3]

Is this the same stuff Steve, I had heard that this was safe?
http://www.bathpotters.co.uk/productdetail.php?pid...

[Spid]

Try Acoustafil used it in a exhaust for my porsche, still going strong. Is worth wrapping the perf tubes in st/steel wire wool first, packing will then last longer
E-mail for Acoustafil [e-mail]

[Steve_D]

Pb3 said:

Is this the same stuff Steve, I had heard that this was safe?
http://www.bathpotters.co.uk/productdetail.php?pid...

No, I think the stuff referred to was a loose fibre fill. See this thread.

Have cut the first box and found that you have to go in from both sides as the gap between the tubes and the outer skin is only about 15mm.

Box cut open.
Beware there is a bulkhead in each end of the box so don’t make your opening too long. The back bulkhead is 54mm from the box end but the front one is 77mm so can catch you out when you position your opening centrally along the box. Just got away with it on mine. My opening is 260mm x 110mm.




Removed packing. Plenty of wire wool but the only wadding was where it was packed into the gap down the side between tube and skin.


Wadding only about 6mm thick.


Steve

[Ramthorne]

Is the SS wool fitted to protect the lagging or for the sound properties? I'm looking at my silencers at the moment, they are repackable, perforated straight through pipe with lagging that is similar to a wood burning stove rope. I don't like the sound at load on higher revs, it sounds a bit 'flappy' I'm not sure if this is due to some gaps in the packing, types of packing, lack of cross over pipe, design of silencer/exhaust or a combination. I've been pricing up Borla and Corsa silencers but they are a fair bit for something that won't make me quicker, especially if the sound can be changed with different packing.

drive past

[Pb3]

Yep that brings back some memories, although I had a little more left in mine than that. What was funny is that I found a dog end inside, it had survived better than the wire wool! I wonder how good a silencer packed with filter tips would be?

[Steve_D]

Ramthorne said:

Is the SS wool fitted to protect the lagging or for the sound properties? .......

Yes. If you don't have something like the wire wool then all the wadding gets blown out. If you used a matt type wadding it may stay in place better and may also be more uniform so eliminating any gaps.

Steve

[GTWayne]

Pb3 said:

...I wonder how good a silencer packed with filter tips would be? ...

I think it may well cause unnecessary drag leading to the motor running out of puff but I may be totally wrong and once the touch paper has been lit it could all go up in smoke.
It may also be worth considering, in the unlikely event that your are overtaken on the road or on track, that someone could rightfully say that they had 'kicked your but'?

[UltimaCH]

GTWayne said:

.....the touch paper has been lit it could all go up in smoke.

A new type of after-burner??

[DHGTR]

Pb3 said:

Yep that brings back some memories, although I had a little more left in mine than that. What was funny is that I found a dog end inside, it had survived better than the wire wool! I wonder how good a silencer packed with filter tips would be?

and with fags at a fiver for twenty , it would probably be cheaper to buy new silencers every year

[Captain Slog]

DHGTR said:

and with fags at a fiver for twenty , it would probably be cheaper to buy new silencers every year

Is that whats called picking up the 'tab' ?

[BogBeast]

Old topic I know, but I came accross this completely by chance:

http://www.thermalvelocity.co.uk/Silencer-Packing/...

[UltimaCH]

Looks good, but will it last?

[spatz]

I talked with the guys at culimeta.de and the acoustafil is good for 450 degrees, I assume that since fibers usually go to 800 degrees it will be gone even quicker in an Ultima exhaust.I have opened my GD exhaust yesterday and it was empty apart from some pieces of melted fiber and the wire wool, that surrounded the inside perforated tube.
I found some stainless steel wool that is rated either 800 or even 1200. Might be an idea for the high temperatures in an Ultima exhaust ?
Anybody tried that ?

[spatz]

ok found a manufacturer here in south of germany that is producing stainless steel wool with 1200 degree
withstand temp. They were telling me that there is quite some customers returning back to this "old" technology.
I have ordered a spool today, will update the repacking thread with some pictures.

[spatz]

Hi Steve,

how did you seal the opening. I assume the cover alone does not provide enough seal.
Is there a glue or better a glass fiber filament, found some from heating appliances to seal the door of a fire door ?

[Steve_D]

spatz said:

Hi Steve,

how did you seal the opening. I assume the cover alone does not provide enough seal.
Is there a glue or better a glass fiber filament, found some from heating appliances to seal the door of a fire door ?

Just used the paste you by to seal exhaust pipes. Called 'GunGum' here in the UK.
Next time I do it I will use the high temp silicon sealer you can get for exhaust use.

Steve

[chucknorris]

When it comes to exhaust packing, what you need to look for is a woven mat type filling.
It's sometimes comes in a form called needle felt as well which is okay but the best type is one that's stitched together to form a sheet.
Do not bother with loose strand type fillings, it will all get dragged out through the baffle pipe in no time at all. The wire wool does not need to be high temp, it's only there to slow down the packing fibres from getting sucked out by the high speed exhaust gasses. The best exhaust manufacturers don't use wire wool, they tack weld a micro-fine mesh around the baffle pipe which has been known to stop and fibres getting dragged out of the exhaust completely.