| I have been battling a noisy valvetrain as a result of worn out VTC cam gears and during the process of installing a newer set I decided to take the time to make them adjustable. There are obviously the alternatives that would have fixed the VTC noise, such as the Jun adjustable cam gears, but none of the aftermarket intake cam gears have the hydraulically-actuated helical gear advancement mechanism to provide the extra "grunt" in the bottom end and midrange RPMs due to the intake cam advancement while also allowing the engine to breathe freely during high RPM operation with the intake cam timing retard. Solution: Make the OEM cam gears adjustable. I did this to Russell Floyd's TT engine in is convertible a few years back when we were building it and I've spoken about the process a couple of times, but never gave a good breakdown on how it is done. It is a rather simple process, but requires a welder which most people dont own. Regardless, any welding shop would do the amount of welding necessary for $20. This will only work if you have the 1994-1995 VTC cam gears as they are a 2-piece design that allows for adjustment. Previous model years are a 1-piece, non-adjustable design. Unfortunately you cannot put the 1994-1995 VTC gears on previous year model camshafts as the camshaft hub is of incompatible length. The articles:
 RearView of the VTC: the slots could be enlarged to allow for even more adjustability, but just eyeballing it with the protractor shows that there is a good 5 degrees of adjustment either way.
 Engraved at 0^ lined to the timing indicator mark. NOTE: You want to mark your dead-zero BEFORE you remove the bolts and lose this position. There are 50 teeth on the cam gear, so when adjusting from zero, each tooth is 7.2 degrees. You wont get a full 7 degrees of adjustment, but ~5 degrees is possible at the limit in both directions. This is also camshaft degrees, so you are looking at a maximum of +/-10 degrees of "actual" advancement (since advancement is relative to the crank and the crank turns twice to each rotation of the cam).
 This is the length of bolt I used: 1.150"
 Bolt installed:
 Nut installed: (note that the end of the bolt and face of the nut have been ground to remove the coatings - provides for a good, clean weld)
 Nuts welded:
 Limit of advancement adjustment: appx 10 crankshaft degrees in both directions from zero. In order to loosen for adjustment, the nuts welded to the bolts are turned clockwise.
 Given that the center hub is connected to the camshafts and it will be very likely that the camshafts are loaded by the valvesprings when you make your adjustment, you need a method of controlling the position of the hub relative to the gear. I found a pair of 17mm flangenuts and TIG welded them to the front of the VTC coverplates and copy-chrome plated them for appearance.
 And here is the final assembly:
The car is still down at the moment as I am re-designing the electric water pump's bearing/seal housing to fit a more conventional type of pump shaft seal - that thing has been leaking for a while now as I've been researching some other options. I have a new mill/lathe coming to me soon which I will use to build those part (and many, many more goodies as well :) In the meantime, I have actually set the VTC's to full retard position. As she stands, there is so much bottom end torque that it just blows the tires loose in anything less than 3rd gear (r-compounds still waiting to be mounted, Luke :)
Once she goes back together and everything is tight, I will be venturing up to the dyno to play around with this, generate some test data, and test how this DXD Feramic clutch stacks up against the RPS clutch I had in there before (which was slipping at 600ft/lbs of torque). I also have a date tomorrow morning with the flowbench, a MAS, and my DAQ setup so we will finally have an airflow vs. voltage map for the MAS. :)
BTW: Admin - the site is running VERY well, thanks for all your hard work!
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