What kind of RPMs are you turning? I finally got enough hours on it to start opening it up and from 52-5500 the rpms are slow to increase and only seeing about 63-34 gps. I didn't stay in it very long due to still being fresh rebuild. It was running much better than that before the rebuild. Headed back out tomorrow and going to change plugs to get rid of the break-in plugs. Hopefully it will do better.