summit is saying that it is balanced for the pre 70 340`s and on the eagle site it is saying to balance it at local machine shop. it was order as a kit for a 360 so i am wondering if they balance their cranks for a neutral balancers and if you what to use a external balancer(360) then you have to have it done locally. eagle do have the sevice offered at there location but the crank was ordered thinking it was internally balanced.if all it takes is a 340 balancer and you can run it as is that would be fine. i don`t have a phone# to contact eagle if someone here has a contact # i would like to have it and call so i can help my freind sort this out.thanks