fooling my small block

Will a tight lobe seperation compensate for the loss of velocity described when you put 340 2.02 heads on a 318?? Large runner/port volume reduces velocity in this combo but a cam on a 108 or a 107 will use the overlap to draw more mixture in, right? but close the intake cycle faster to keep up dynamic compression? Theoretically a tight LSA should balance that loss of velocity within reasonable parameters, right? I have the 318 with 340 J heads, 2.02/1.60 valves and I'm trying to pick a cam for my combo, I have a factory high stall converter, 2.75 first gear, and 3.55's. The cam I was looking at is an Isky 216/445 on a 108. My second choice is a crower #31918, with a 214/224 at 444/467 on a 112. The crower grind will slip in, which is a prerequisite for me at this time, and there is plenty of room for the isky, the only two issues I have are price and LSA. I have run small 50-75 shots of N02 before, but this is only for fun and not criteria. I want a nice lopey 108 sound, too, that's nice. But, people say that with the 108 nitrous is a no no. The true criteria for me is an optimal use of what I have to work with, and the final choice has come down to this, and I could use some more input from the ones who've been here. Thanks again! People tell me not to overthink it but I can't help it, I work too hard on my car, and to earn the parts I get so I hope noone is getting tired of my endless queries!