Oil Leak

Ok anyone else ever expirence this. I'm losing oil extremely bad, but it doesn't happen when the car is not moving I've let it sit overnight on some cardboard to see if I'm really leaking a lot....but it's coming up clean, I'm not burning oil (well nothing noticable) but there is somewhat of a fuckin stain running down the front of the block and onto the transmission meaning that the leak is coming from the camshaft plugs near the distributor (the valve cover gasket is brand new since I put it on myself). Is it entirely possible for me to lose about 1 litre in less than 100kms just from a small leak or what seems to be one and I know for about a good 30km's of that 100 I was pushing the car really hard so would that have anything to do with it.