Didn't know the factory tappets actually have a design flaw. All this while I thought of the tappet noise to be Mitsubishi's signature. Got kind of used to it after using 4G93 for a few years before converting to 4G93T. Both have the same tappet sound.i see, just that i read that the stock tappets have a design flaw so am wondering if the aftermarket ones will silent the noise. yep my engine is pretty much stock as of now