What size generator should I choose? Viki September 14, 2017 07:12 Updated Follow Portable generators - click here for a sizing guide.Home standby generators - click here for a sizing guide. Related articles Can I make my engine quieter? Can I put a GX390 carburetor on a Predator 212cc engine? Comments 1 comment Sort by Date Votes JiaWen Lin September 14, 2017 07:12 Use this tool,you can calculate the wattage easily http://www.quietgeneratorsforsale.com/calculator/ 0 Comment actions Permalink Please sign in to leave a comment.