I'm wondering if it's not the changing the angle of how the KS is ref., to the vibration, rather then the dampening. In which case, going to 90d might even desensitize it more (not suggesting going any further then needed thou). Grumpy > Bruce, > The 45 degree fitting for the Knock Sensors looks like something to try. > Mabey by spacing it away from the block, might calm it down a bit.