try ejaculoid and some other and do a few test firings before the weekend. Leave friday for recovery, maybe thursday if you get carried away on the testing.
Look for not only volume but force pounds per square inch, and distance. war is hell.
there's lots of combo products on the shelves at gnc and vitaminshoppe etc
look for stuff that has hi doses of as many of these as possible:
tribulus
ginseng
avena sativa
maca
horny goat weed (epimedium)
most will also have cnidium monnier and yohimbe which act liike viagra