Exhaust on a petrol generator

[NortonDommi]

Ditto for myavid76 but I would bury an old drum with at least 27 times the volume of one cylinder a few feet underground sitting on a few inches of gravel. Put a drain in the bottom, feed in exhaust from top with the exit about 1/2 way down inside drum and take an outlet pipe from the side about 1/4 down,(plastic O.K. for pipes & drum once 3' or more from exhaust port),out under ground at least 6 feet and up and out. Make sure you have a U-bend on the outlet to stop rain water and screen it to stop rodents and wasps.
You can do the same for the intake and with decent sound insulation you will not know it is running.
I've done two like this for remote camp sites where you can hear a Mossie at 2 miles and it works well. Generators are in concrete block enclosures with sand filling and lids made of 1/2 height blocks sand filled between 3/4" treated plywood with pipe from intake drum to enclosure and then just out about 10' with el cheapo ventalation fans powered directly from generator,(when genset is running so are the fans).