It'* going to sound like I am ZZP bashing. I am not, but have many issues with their sales practices and some of their products. I am trying to point out where other products are preferred.
ZZP double talks all over their site and forum. They are a business and try to increase sales anyway they can. While I do like many of the parts they sell, I absolutely despise their sales practices that go as far as telling customers when things break that it'* an installer error or they've never had a problem in the last X years or X number of them being sold. That'* simply **** poor customer service, kinda like not including cam lube in a cam install kit.
They know how to **** off an installer.
There are hundreds out there running XP cams on single chains. I installed one this weekend. Get a new stock chain or single chain and you will be ok with 105# springs. Watch out which retainers you get, ZZP'* modded retainers with their modded rockers and HD valve locks will hit. My suggestion is ZZP valve seals, Intense'* Manley retainers and Crowe Cam (ZZP or Intense) 105# springs. Comp Cam 105'* were sourced to Mexico a while back, then started breaking. Get the chain, dampener and reuable rocker bolts from either. Gaskets... ZZP'* valve cover gaskets don't seem to fit properly (I put a set on this weekend) and don't come with the grommets. Grommets are there to keep the proper torque on the gasket, they should be replaced when changing gaskets. The gaskets from ZZP were slightly too small for the valve cover and had to be stretched to fit in the channel, I have never found this with GM or FelPro gaskets. Thought if was extremely odd, maybe they have some other manufacturer making them.
A disconnected balance shaft is a lot of vibration in a 3800 motor. Don't forget your RTV and pipe sealant for the LIM bolts. With the right parts the install goes quick and easy.
BTW My car is an informed owner taking a bit of a chance. Typically on 130# springs you would have a double roller. I, like Todd Allen at Intense chose to keep the balance shaft because of the vibration and therefore am limited to a single chain. Soon I will be checking for issues or stretch, until then the car is my toy and it'* an informed chance that I take.