Are these cars like Honda's, in that they require periodic valve adjustments? My valves aren't noisy but was just wondering.

 

No. If it makes noise (and lifter isn't just stuck), then you have to tear it apart and replace w/e is bad (lifter, bucket, shim).

It should not need servicing, ever, although it's been known to happen sometimes (poor oil maint especially).

 

Get you a feeler gauge and check the tolerances on the shim gaps if you like!

 

+1 If it ain't broke don't fix it...unless you're upgrading