the ring doesnt seal by its own preasure, but rather from the preasure of the combustion. the combustion will push the ring against the cylinder wall. the harder you push the motor, the harder the ring is pushed against the wall. Rings are made of a steal that once heated too many times, will become harder than the cross thatch, then guess what, it will wear the cross thatch and wont break in properly. Break your motor in with the first 20 miles, smartest way to do it.