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In Reply to: Valve/ tappet clearances posted by Stevie on April 10, 2000 at 13:44:55:
all s14 m3 motors have noisy ticking in the top of the head for two reasons the valve clearance's are quite large (for this type of valvetrain referred to as shim and puck)as this is the only way for the valve's to transfer heat to the seat, the more clearance the longer the time the valve and seat are in contact at the bottom of cam profile this prevent's exhaust valve burning (especially with the heat generated in this motor's combustion chamber with 10.5 to 1 compression ,which is also why you have to run 92 octane fuel )this is why all high HP racing engine's have noisy valvetrain.the second reason you're s14 is noisy is that the whole area under the valve cover is open and this acts like a resonance chamber making valvetrain noise louder. i have adjusted the valves on my s14 on the tight side of tolerance (because i check them frequently this is not a problem)and its still noisy there just no getting around it more HP=more noise enjoy it! note if you havent adjusted your's lately do it just to make sure they are in spec.