Hey guys I had a motor built maybe two years ago and I need to replace the balencer. I am fairly sure that the builder Keept the motor internally balenced but not 100% sure. I do know that there are some small holes where he drilled the balencer for whatever reason can any one helpe out?

 

The holes could be to balance the damper itself. That's what always used to get to me when people said there were LT1's that were completely externally balanced and the proof were the holes in the damper... even though the damper wasn't keyed...
Anyway, yes theoretically your motor should be internally balanced at least in the front and the damper should be zero balanced. You can either call the machine shop who built the engine and see if they still have the build sheet for it or you can have the damper spun just to make sure it is zero balanced.