M Type exhaust silencer/expansion box.

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garagiste
Posts: 93
Joined: Wed Jun 15, 2011 8:22 pm

M Type exhaust silencer/expansion box.

Post by garagiste »

I am making up an M type exhaust system, not being a purist, I propose to use a modern silencer/expansion box.

I have a most useful and tolerant exhaust specialists locally who can normally find a modern box of approximately the correct dimensions and type.

Was the original a straight through expansion box or were there baffles?

Any suggestions of a modern box that anyone has used?

David.
ian judd
Posts: 176
Joined: Tue Jan 08, 2008 6:01 pm

Re: M Type exhaust silencer/expansion box.

Post by ian judd »

If you were being purist you wouldn't have much luck since the original silencers haven't been available for many decades. It seems two makes were supplied, Burgess and Vortex. I don't know how the Burgess is made or what one looks like, but the Vortex appears in many period photos. I have just had one repaired just to hear what it sounds like; I intend to take it off again and cut it up so that I can make a new one.
It has not been on long but I now know it is about as effective as the straight-through it had on before but much quieter. As the name implies, it contains a series of interlocking cones which induce a vortex. It is much larger than the silencer supplied by S+V. I will take some measurements later on and post them.
I'll see if I can include a photo - my attempts so far have been 'invalid'!
Ian Grace
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Re: M Type exhaust silencer/expansion box.

Post by Ian Grace »

Ian just sent in this picture of his Vortex. The other three images were sent to me by Ian in 2006 and were published in M 124.

Looks like quite a complex piece of kit to replicate - more like a wind instrument than a silencer!

Minors were fitted with conical-ended silencers that had much simpler internals, and replicas are available from the Cooke Group.

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ian judd
Posts: 176
Joined: Tue Jan 08, 2008 6:01 pm

Re: M Type exhaust silencer/expansion box.

Post by ian judd »

Ian, thanks for putting those photos in. I had forgotten about the earlier ones. For anyone looking for a similar sized one, the length of the barrel is 15" and the diameter 4.5".
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