[vonsmog]

I have an 8 HP 4400 watt generator that I will run inside the basment of my shop if the weather is real bad. I made up a 1 3/4" flex pipe for the exhaust. This bolts on in place of the stock muffler. I then past the pipe out through a hole in my garage door and have a old muffler I picked out of a dumpster at the muffler shop, slipped on the end of the flex pipe. It is very quiet, and I can't even hear it running in the house. The generator makes a lot of noise anyway being air cooled. So I think the exhaust is only a small part of it. When it is running in the shop you need hearing protection when in the basement.