I am presently tuning a 2014 Raptor 6.2(6) and know how to tune the spark and fuel, but the VCT/VVT tuning is a mystery to me!
I can't seem to find anything that truly explains how Ford VCT actually works regarding tuning. I've successfully tuned many GM and Dodge VVT equipped engines, but I can't figure out how to advance or retard the overhead cams at any RPM or Load level.
In "Mapped Points", what does "Snap to Point" and "Snap to Line" mean? There is nothing that relates RPM and load to Mapped Points 0 - 4. Apparently, based on "Mapped Points Config," MP 5 - 14 are not used, as they are not enabled.
The "Intake Valve Opening" table and the "Exhaust Valve Closing" table should agree, since these engines have only one camshaft per head, to operate both intake and exhaust valves. Intake Valve MP 10 has 34 deg, but the Exhaust valve has 43 deg for the same MP 10, so that looks like a mistake from the factory. But other than that, if these numbers show MP 0 = 0 deg, MP 1 = 13, MP 2 = 23, and MP 3 = 33 deg , and they are all positive, does that mean the cam is advanced or retarded by that amount?
What do the "Distance Tables" do? They are based on RPM and Load, but the numbers vary from 0 - 4.00. When these values are higher, approaching 4.00, what should I understand about what the higher value means? What would happen if these values (of 4.0) were raised higher to 5.0 or 6.0 max? What would that do?
[ECM] 38158 - Optimum Power - Intake Valve Opening Angle vs. RPM
[ECM] 38156 - Optimum Power - Exhaust Valve Opening Angle vs. RPM
Both of these tables should agree and they do. They both have the same data: 500 - 3500 RPM shows 0 degs, 4500 RPM = 8.0, 5500 RPM = 12.0, and 6000 RPM = 18.0 (again not clear if this means adv or ret). I hope that doesn't mean that by 6000 RPM the cam is actually supposed to advance the cam by 12 degrees. If anything, the cam should be retarding in the upper RPM band to reap the best power at that point!
Thanks for any assistance provided!