Notfishin 64 #1 Posted July 10, 2017 Morning working on Exhaust . on a magnum 12 there is a exhaust flange . i need to know the outside diameter of the pipe . im going to exhaust shop this morning . and need to know what size pipe i need . Thanks guys . ps i should have measured it this morning before i left for work . Share this post Link to post Share on other sites
Ed Kennell 35,770 #2 Posted July 10, 2017 Hmmm. I just looked at my Mag 12 on my 312 and there is no flange . Mine has the pipe thread in the block with a short 45 elbow with a 1 7/16 OD pipe that the nelson muffler slides over and clamps to. 1 Share this post Link to post Share on other sites
Notfishin 64 #3 Posted July 10, 2017 Morning ED yes i have a k series 12 hp that has a piece of pipe also in it . but this magnum has a piece that looks to be a factory elbow where the muffler clamps on to . Share this post Link to post Share on other sites
Ed Kennell 35,770 #4 Posted July 10, 2017 Like this? I would have to remove the muffler to measure the OD of the pipe on the 45 elbow, but the ID of the same nelson muffler measures 1 7/16". 1 Share this post Link to post Share on other sites
Notfishin 64 #5 Posted July 10, 2017 Yes . That is IT Thanks ED Share this post Link to post Share on other sites