Lol if I were in your position, I'd just go balls deep in the XPZ build, and with the coin saved from not doing the vs build, get a good trans. However, i still understand and respect what you're doing. Granted I've seen mostly turbo guys with the XPZ cam, but they still report good street manners and about stock, or slightly less mpg.(I have the NIC cam with the more aggressive idle and I still consider it good street manners).
From what others have said on the board, even with the higher pressure, the 105's are easier on the chain than 90's. However I had a 1.9 HS rockers with ls6 springs for about 100k and when I did the NIC swap, the stock chain had little wear considering the rockers and springs choice. If you're looking for 240-250whp on 91, the VS cam *should* work considering if you'll have a 3.4 setup and other supporting mods. E85 could be a good game changer for you, and could easily gain you some power over the other cams instead of going with a VS. however I have no personal experience with it, so I'd ask other members about it who actually use it.
In a nutshell, I'd suggest doing this for cost effectiveness, an going along with what you're looking for.
Vs cam
L76 springs(about the same, if not cheaper than ls6 springs, and offer less wear on the chain)
Ls retainers
stock lifters *should* be good if they only have 100k, the vs cam isn't that aggressive and as long as the stock lifters are in good shape you could keep them. But FYI ls7 lifters are awesome and cost about $100.
Ported blower outlet
slp headers
180 tstat
104 AL plugs, or any other same heat range plugs
E85 would be sweet
and whatever pulley you can safely run with 16-18 degrees of total advance wot timing. However all cars are different and may like more or less timing.
Get the bigger injectors. You can tune them with 250whp, and this way you'll be a tune away from running e85, instead of doing that and swapping injectors.
Trans. Rock the stocker for as long as you can with a good shift kit and a cooler. The next cost effective way would be a "basic" TK trans. Which goes for about $1300 shipped, no core. (that's about what I paid). I'm not a fan of junkyard transmissions, unless you know for sure it's a low mileage one. Anything more than 50k I'd pass on. I just don't want to take the risk, but that's just me.
