QUOTE(930cabman @ Sep 5 2021, 06:43 AM)
I will be calling Kennedy Tuesday, see if they can confirm a 0 balance on their pressure plates.
Nothing in life is zero balance. Even if someone tells you it's zero balance, there is still a tolerance to the equipment and process used to balance. Go measure same zero balance part on another machine and it's highly unlikely you'll get true zero.
Fully agree a fully dynamic balance of all rotating mass is ideal. Mandatory for high RPM race engines.
However, are you also having your fan dynamically balanced as part of the assembly? If not why not? Inclusive of fan hub and fasteners? Will all flywheel and pressure plate fasteners be placed back into exactly the same holes they were blanced in? You see where this is going.
As stated previously, for a road car, in normal production, components are balanced as individual parts. There is a print tolerance on each part and each part has a six sigma variance of what it could be in actual production. A Monte Carlo simulation can be used to understand what the final balance liklihood is of a given outcome. Most times, some parts will be a little on the plus side, some on the minus side. Same with respect to how they index. In the end, it all works out within an acceptable range due to the statistics and probability working against all parts being all on the plus side or all parts on the minus side simultaneously.
Not saying that you shouldn't dynamically balance. However, let's recognize that OEM was not built that way. Full dynamic balance is nice to do for a road car but not a necessity. My first rebuild wasn't dynmaically balanced, I had neither the money to do it nor access to a vendor that could do it back in the day. That engine ran about 100K miles, no issues.