| and nothing else so here it is. Sorry for beating a dead horse but please beer, uh, I mean, bare with me. I don't believe Ash has actually created a new super fix for the VTC noise problem but rather he has fixed the problem using something that was already allowing the fix to happen. I think it was staring him in the face and he just didn't see it. In the picture below Ash basically used newer designed and less worn VTC sprocket internals for his fix. You can also see that the older VTC internals he had replaced are quite worn out. Look at the spline alignment on the old "piston helix" I have circled in yellow. Just sitting there the splines are aligned when they should be staggered from the internal pressure of the six springs as it is with the new one. This is a sign that the six springs inside that piece are shot. The pressure of the springs would certainly add to reduce noise, slop and distance of the "cam helix". If you look at the old "piston helix" where I have circled it in green, you can see that the thickness is much thicker compared to the new one. This is because the new "cam helix" circled in red now has a collar. The reduced thickness of the new "piston helix" compensates for the thickness of that collar. Now for the part that keeps it more quite. The collar on the new designed "cam helix" acts as a stop keeping it from traveling to far in to the "piston helix" where the older "cam helix" was able to travel deeper making more contact. The collar also makes contact with the surface of the "piston helix" so now as the outside spring pushes on it the "cam helix" will be putting pressure on everything because of the collar. This will help reduce noise and slop even further. Ash saw the problem of how the old "piston helix" and "cam helix" was wearing out the end plate so he made a new end plate with built up surface area to keep the "cam helix" further out and to help take up the slop. Ash's fix was basically replacing the old end plate with a new one with less wear and using the internals of a newer designed VTC sprocket with less wear which also didn't allow the "cam helix" to travel in as far with it's collar. You could in effect accomplish the same fix by replacing a worn out VTC sprocket with a new designed one. With the newer designed internals Ash used, he may have fixed the problem without even needing to create a new end plate due to the better condition of the newer designed "piston helix" and "cam helix" having a collar stop. JWT's fix with the stiffer outside spring was to put more pressure on the "cam helix" to stiffen up the slop. This may work better with the newer designed VTC sprockets because of the "cam helix" collar appling pressure on everything. I read many post on the web where people had success with this fix. But other people say it had no effect at all. I believe Ash's fix will last as long as a new sprocket would last but only as long as he uses new updated internal sprocket designed parts. I don't think it would be posible to obtain these new parts and be able to sell the modified sprockets at the price of $300 as he inferred. You might as well just buy a new designed sprocket. Below I have included the Nissan technical bulletin on VTC noise. There's not really much to it. They say to replace the outside spring. I looked through all my tech bulletins and could not find anything on a newer designed VTC sprocket. I believe that during the first few years of the Z32, this was a know issue and the fix was presented as it was in this bulletin and for the earlier years a design change was implemented in the VTC sprocket internal design to help reduce the posibility of noise even further. Anyway, Ash wanted my input, so here it is. Is it completely factual? I don't know, it's just my therory of observation. If anything, I think we have all gained much more insight as to how the whole VTC thing works. I DO know that if the VTC parameters are played with in tuning an ECU you had better be very carefull because the wrong settings could very well cause broken valves. NTB92_016_1MJ39_300ZX_INTAKE_CAMSHAFT_SPROCKETS_CAUSING_TAPPING_NOISE.pdf 
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OK, Ash wanted my input on just the VTC noise - 
