Brookland style mufflers

[jansens]

I need to look at fabricating the exhaust for my car and my current plan (which could change) is a sports style pipe running along the nearside of the body. The body style I have gives me plenty of space to mount it there. Actually I have so much space it needs something there to break it up! I just need to make sure the wheel doesn't hit at full lock I think. 

I know of this page that describes the origin Brooklands style silencer and fishtail: http://www.austin7club.org/How%20To%2011.htm

My thinking so far is 1 inch tube from the block into a 1 1/4 inch collector and from there into the muffler and a similar size tail pipe. The actual tube I have is sold as 25.4mm OD and the bigger pipe would be 31.8mm OD both with 1.2mm wall thickness so that seems about right. I would slit and taper the collector part.

The pipe seems so small and I know that silencer was only for Brooklands but I guess that is right for a small engine. I can work out the dimensions from the link above but was wondering if someone who has one can post general dimensions. My car isn't a replica of anything so I can make whatever I like that is in period and functional, it's doesn't have to be an exact copy of an original.

The pic on the radius arm thread reminded me to ask!

Simon

[Chris KC]

Simon, for what it's worth the 'Ulster' silencer was approx. 13" long, 4 3/4" high and 2 1/2" thick.
The ends were domed with about 3 - 3.5" radius in side view.

The outlet pipe is 1" OD, connecting to a 1 1/8" OD tailpipe. Not sure about the inlet, mine is 1 1/2" ID.

Chris Gould's Ulster Replica book contains suggestions on how to go about making one.

I think Ian Bancroft sells a similar silencer, like most the ends are flat as it's much easier to make.

[jansens]

Thanks for that, gives me some idea of the size I am dealing with. Public holiday tomorrow so I should get some car working time.

Simon

[Derek Sheldon]

    This is the Chris Gould pattern on a special that I built 30 years ago, I added the jointing flange at the rear. Still have the dimensions etc if you require them.

[NBS]

Simon, for what it's worth the 'Ulster' silencer was approx. 13" long, 4 3/4" high and 2 1/2" thick.
The ends were domed with about 3 - 3.5" radius in side view.

The outlet pipe is 1" OD, connecting to a 1 1/8" OD tailpipe. Not sure about the inlet, mine is 1 1/2" ID.

Chris Gould's Ulster Replica book contains suggestions on how to go about making one.

I think Ian Bancroft sells a similar silencer, like most the ends are flat as it's much easier to make.

Did the silencer have any silencing material in it or was it simply an expansion box?

[Chris KC]

It's just an expansion chamber.

[jansens]

So do they actually silence at all?

[Chris KC]

'Silence' might be over-stating it...

[jansens]

Vague muffling is good enough!

[Bill Sheehan]

Vague muffling is good enough!

Back to the good advice and measurements on making your own - I've been led to believe that the Longbridge factory made (or had made) in the latter days of Ulster production - the ends flat, not compound-curved.  Can't prove that statement, but some photos seem to show the flat ends - worth checking as much easier/quicker to make.   Look for photos of the later versions, where the back rest is straighter than the earlier curved ones.  Good Luck, Cheers,  Bill