Muffler gasser 0a-331

[johan77]

Hi guys,
Best wishes for 2025,
My question, the muffler on an m35 with oa-331 gasoline engine has 2 different diameters in connection. A big one and 1 that is significantly smaller. Is the small one the intake? And the big one facing the rear part tailpipe that exits between the rear wheels ? It does not say on the muffler what side is in and wich one out. Also nothing in the manuals. From the manifold till the end is nothing standard anymore , previous owner made custom build piping with a tiny muffler, wich was completely rotten , so i bought a nos muffler for the gasser engine.
Thanks !

 

[NDT]

Doesn't your new muffler have 3 bolt flanges on it? The diameter on the inlet will match that on the exhaust manifold.

 

[gringeltaube]

Front exhaust pipe section (between engine and muffler) is 2-3/4" OD and what follows passed the muffler measures 2-1/2" OD.

 

[johan77]

Thanks a lot , now i know to intstall it correctly , should be more quiet when running haha

 

[johan77]

Doesn't your new muffler have 3 bolt flanges on it? The diameter on the inlet will match that on the exhaust manifold.

Yes, but the original pipe was cut off, they used the 3 hole flange and went from there with regular steel tubing.