No adjustment is needed, you have hydraulic lash adjusters. If the valvetrain is noisy, one of them may need to be replaced or is gummed up. If you have a good OHC valve spring compresor (KD tools makes a great one that I use, I'll get the p/n off of it when I get home) you can try swapping them out yourself. They slide right out of the bores once you have removed the follower.