Fordiesel69 233 #1 Posted January 10, 2014 I notice on the K321 / M14 that have a much larger ex valve. Looking equal in size as the intake. Can any power increase be had by enlarging the exhaust valve on the 12HP models and swapping carbs? Share this post Link to post Share on other sites
shorts 182 #2 Posted January 10, 2014 You need to keep your exhaust valves the same size to keep the power band where it is, when you start playing with valve size and camshafts you will change the RPM that they produce power, Most small engines are power adjusted and tuned to work at 3600 RPM to provide maximum compatability with the accessories Share this post Link to post Share on other sites
