Rotating assy balance

yeah they are heavy old school pistons . there are a lot of good pistons out there today that are lighter and stronger , once you're spending money do it right once
Nothing wrong with speed pro pistons! Especially the 116 they are very well made and perfect for a budget performance build! For a 360 the 116 +30 pistons weight very close the same as factory you can run them without any balance work done to to he bottom end. For a mild street engine anyway.