Dusty
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| posted on 30/9/06 at 08:49 PM |
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More noise reduction.
Currently have a four branch manifold into a 2" inch pipe then 6" x 17" custom chrome(rust) silencer. I have a five inch silencer
which I have just cut up to make an extra box between manifold and silencer as per pic. This can have a perforated through pipe, with or without
wadding or just be an empty expansion box.
Anyone have ideas about which would be best for additional silencing bearing in mind I can't afford a new silencer at present and this is
'free'.
Any ideas which format is most effective on silencing and if there is likely to be any effect on performance bearing in mind it was not a tuned length
before and still wont be one!
Rats. Still can't add a pic to posts I start. The box doesn't appear. I will add to archive.
[Edited on 30/9/06 by Dusty]
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smart51
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| posted on 30/9/06 at 09:36 PM |
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I would have thought that keeping the perforated pipe and packing would be best. Its just like having two silencers. I would have thought that one
long silencer would be better than two short ones but if its free, I guess two is better than one.
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rick q
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| posted on 30/9/06 at 09:43 PM |
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I built my silencer using a gutted Yamaha R1 can. The first time I had a simple perforated core (lots of little round holes) with wadding and it was
LOUD. The second version used a louvred core (like lots of fingernail sized air scoops) with the open end of the louvres facing the engine - much
much better. Stainless mesh also lasts whereas fibreglass wadding just dissappears.
see http://www.locostbuilders.co.uk/photos.php?action=showphoto&photo=IMGP2718.JPG
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Danozeman
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| posted on 1/10/06 at 11:38 AM |
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Image deleted by owner
I would fill it with wadding using the perforated tube. TBH though i dont think the extra silencer would make a great deal of difference if your big
one is packed well.
Dan
Built the purple peril!! Let the modifications begin!!
http://www.eastangliankitcars.co.uk
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dave r
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| posted on 1/10/06 at 11:49 AM |
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have recently fitted 2 volvo front boxes to mine.. cost less than 40 quid, and an hours work
made it so quiet, i can hear the gearbox front bearing is on the way out!
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NS Dev
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| posted on 2/10/06 at 10:48 AM |
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quote:
Originally posted by rick q
I built my silencer using a gutted Yamaha R1 can. The first time I had a simple perforated core (lots of little round holes) with wadding and it was
LOUD. The second version used a louvred core (like lots of fingernail sized air scoops) with the open end of the louvres facing the engine - much
much better. Stainless mesh also lasts whereas fibreglass wadding just dissappears.
see http://www.locostbuilders.co.uk/photos.php?action=showphoto&photo=IMGP2718.JPG
Louved pipe pointed at the engine like that absolutely kills hp!!!
The flow reduction is HUGE, much more than you will expect.
Will be very quiet, but needs turning round once tests etc are passed!
Retro RWD is the way forward...........automotive fabrication, car restoration, sheetmetal work, engine conversion
retro car restoration and tuning
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Dusty
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| posted on 14/10/06 at 01:01 PM |
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Fitting the extra little box made a big difference. Went with perf tube and packing in the end. I should think it is easily down to 95ish db.
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smart51
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| posted on 14/10/06 at 01:19 PM |
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how loud was it before? How long was the extra box that you fitted? I might be able to do something similar, if I needed too.
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Dusty
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| posted on 14/10/06 at 11:24 PM |
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Around 100db. Box is 8" by 5" dia straight through plus tails to mate it into the 2" system. Effect exceeds all expectations. Easy
fit for trackdays when you are tight on noise. Don't know about power loss till my next RR session but nothing obvious.
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