vtec9

theres a good chance what you're hearing is the injectors, which are always noisy in the S.

CoralDoc

I have performed over 15 valve adjustments on F20C engines (and a couple on F22Cs), and nearly all of them benefitted, even those with relatively few miles (under 20k). On most engines the intake valves were close to or slightly over their maximum specification. When set at the minimum specification (0.008" intake and 0.010" exhaust), the engine typically run smoother and with slightly less clatter. Some noise is normal. Some owners report a slight increase in power based on their butt-dyno. Since it sounds like you know what you're doing with cars, why not do an adjustment on your engine and report back to let us know if it helps. I adjusted the valves on my car for the first time at 15k miles, and it smoothed out.

There is a write up on valve adjustments in the FAQ for the F20C, and I think it's the same for F22Cs.

hisport

Thanks, everyone.

Joshua - I will do as you suggest and report back, especially as it appears that i don't need a set of shims, etc to do the procedure.

john