- Oct 22, 2003
- By Detroit
I have a V-twin Generac engine on my motorhome generator. The engin is a GN-480. Anyway, I need a new muffler. Now I happen to have a brand new muffler similar to the one that is on it. The new one is smaller. Here are the dimensions: (Old, New) Width: 4", 4" Length: 16", 11" Inside diameter of pipe entering muffler: 1", 1" Inside diameter of pipe exiting muffler: 1.375", 1" So, my reasoning is 1) A smaller muffler is not necessarily more restrictive (I can do a blow test through each muffler). 2) The smaller outlet on the new muffler is not a problem since both mufflers already are restricted to that size at the inlet and as the gasses flow away from the engine they cool and thus take up less space. What y'all think? Am I being a tight wad? Or is it reasonable to run the smaller muffler?