Hi can you help. A friend has asked me for measurements of the hole placement on the inners of a veteran cast muffler - can you help?

"Have the muffler to pieces and there are 2 inner pipes missing, 1 is 50mm dia and the other about 80mm. Question I have to put some holes in the 2 inner pipes but what size and where they go I don't know, can you help or perhaps its a question for the forum."

Thanks in advance
Simon

They look like about 7/16" inner holes and 1/2" on the other. Perhaps you can deduce for this link. Click on the pictures for a larger image.

http://www.modeltford.com/item/4025SE.aspx

Do you know how many holes per piece?

Simon, I make repro mufflers locally and use a 7/8" hole saw to make the holes, two at the back end of the inner pipe and two at the front end of the second baffle/sleeve.

Hope this helps.

Allan from down under.