340 pistons

I got 10:1 w KB107s, 68cc X heads, and a Fel Pro .039 head gasket. KB243s would be a little higher. With the cast crank and the light pistons it winds up real quick (light rotating assembly). I was told not to turn a cast crank over 6500 RPM. I will sell the complete engine for $1800. Only has 2500mi. on it. I will be swapping engines in my car within the next couple weeks.