Pretty much the fastest you can get it is 1stack per tick. Diamond autarchic gates on a wooden transport pipe will do that. As will combustion engines. Same with precision import buses.
However, if I'm right that you are moving the output of a quarry or other mass resource collector into your storage/processing chain, the fastest way is by abusing ME interfaces. While an ME interface won't "pull" from an inventory on it's own, if you "push" items into it, it will accept them as fast as you can chuck them in. So if you have a quarry, instead of trying to pull from an inventory that the quarry empties into, just empty the quarry directly into an ME interface. Or empty multiple quarries into several Item Tessaracts (set to send only) that are linked to a single Item Tessaract (set to recieve only) that's next to an ME interface. You can get infinite speed and throughput that way.