It`s called BLOW BY - if it`s coming from the Valve Cover Breather Vents and is as obvious at idle as you say then you definitely got an engine problem.
Was the engine built by a shop that is in the busness of rebuilding engines or was it Joe Bob and Cooter out back of the barn? its a shop that is in the engine rebuild business, they build engines for 1/4 mile races here in Monterrey Mexico. they ported the heads let me take a video of the engine smoking and post it, so that all of you take a closer look . thanks:Handshake Nelson Etienne