| Here's a link to my last VTC post Fact: The intake Valve Timing Control (VTC) broadens the torque curve of the VG30DE engine. By locking it out with JUN or Tomei solid type sprockets, you throw away usable power in the mid range. Fact: When used with upgraded cams and/or higher pressure valve springs, the VTC sprockets make a ridiculous rattle that makes the car sound like a piece of shite. Fact: New sprockets from Nissan cost ~$900/pair and they have the exact same problems as early model sprockets. Those of you living with this noise will soon have the option of retaining the variable valve timing quietly instead of abandoning the VTC sprockets altogether for solid/adjustable types. And, as most of you may know, the current fix of installing a heavy duty "VTC spring" does not cure the problem. The problem is an internal spring to the sprockets and Nissan made them as sealed units making it nearly impossible to get at the spring to fix the VTC rattle. The solution: Cut them up and see what can be done to make them servicable. Another issue is oil leaking from the back of the sprockets which is often assumed to be a bad cam seal. What's wrong here is the back cover is not held tight enough and it spins eventually wiping out the o-ring. The solution: prevent it from spinning. Currently I'm testing on several cars using JWT and/or Ferrea valve springs with JWT +400, JWT 500 and custom 10.25mm solid lifter cams before releasing the sprockets for sale to the public. All of these cars are running stock front VTC springs and do not exhibit any noise AND the VTC is fully functional. Estimated date they will be available is by the end of this year; at which time we should have sufficient running time on the test vehicles. Initially only early model sprockets will be available since these are by far the highest percentage out there, eventually I plan to service the late model sprockets and offer an adjustable form of the early model sprockets (see my link above). If anyone has any old sprockets laying around, I am buying them as cores in this classified add. Early style VTC, note the dowel pin to prevent rear cover rotation
Late style VTC, note these are semi-adjustable in stock form. My modification relocates the bolts to the front of the sprocket for easier access.
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VTC sprockets, killing the rattle - 
