[Mike Simard]

BinB, it's not unheard of for breathers to fly off during dyno runs and it may not be a problem, there will be some blowby even if the rings seal well. If you had detonation problems it's possible to have damaged a piston. Why not do a compression check to find odd cylinders? You can have a detonation damaged piston with chunks broken off around the ring land and not even know it, you would want to catch it before the ring breaks up.