| The purpose of degreeing the cams is to set them to a known baseline prior to any dyno tuning. I developed the 3rd element timing indicator so a tuner could see how far they were adjusting the cams from a baseline degreed setting. Because the VG is a V engine with two separate banks of cylinders with 2 cams per bank (4 total), there are several methods to tuning its cam timing:
1) one cam at a time
2) pairing the exhausts and tuning both the same amount (or pairing the intakes to tune both by the same amount).
3) adjusting all 4 cams the same amount at the same time (this is the same as how a single cam engine would be tuned and doesn't take advantage of separate intake and exhaust cams). Worst case scenario: cams are not degreed and the tuner uses #1 method from above.
If the cam timing starts all over the board for all cams and the tuner starts with an adjustment of the USDM driver side exhaust cam (for example) to make the most power, while the other cams are still all over the board, this "tuned" setting for this single cam will most likely not be what makes the most power when the rest of the cams are tuned in the same manner. This is just sloppy tuning, plain and simple. Best case scenario: cams are degreed and the tuner uses #2 method from above.
In my opinion, and especially with a 4 cam engine, the ultimate goal of cam timing tuning should be to find a setting the makes the most TQ at the RPM of interest with the tuned cam timing for each exhaust being the same and each intake being the same.
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