NOS? sure it's connected and usable? if it is, i would suggest reading up on it before you do anything you'll regret, and more than likely there could be a problem if the owner was running it hard, and find out how much psi you're running... or else it will be zoom zoom boom for sure. just some info for the new guy.
edit:
looked at the pics closer... and it seems to be hooked up. you might want to take a deeper look into the block and check out the rods if you can. also, what gauges are you running, i see 4? and not sure what is up with the duct tape but might want something more secure.
welcome to the boards.