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Old 04-12-2011, 12:15 AM   #24
thePill
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Drives: '11 Mustang GT Premium
Join Date: Oct 2010
Location: Kaiserslauthern, Germany
Posts: 1,268
I'm going to attempt to explain this Cam in Cam operation. First, this CiC has nothing in common with VTEC, CiC does not alter the lift at all. VTEC was technically two cams in one, when a certain RPM was reached, a secondary lifter would lock into place on a secondary lobe that had a much higher lift. Honda's VTEC usually dropped its secondaries around 4500rpm, at which a higher lift was used only, duration could be altered depending on the secondary lobe and timing would remain the same.

Cam in Cam (CiC): This setup is made of two cams, a hollow exterior cam (hollow like a OHC's cam) and an internal solid cam. I don't know for sure but, the exterior cam would control all the intake valves and the internal cam would control the exhaust (could be the other way around). The VVT phaser (or the strange casting that surrounds the cam gear and adjust the cam timing) would contain two separate cam phasers for each cam. Probably a large outer phaser for the hollow exterior intake cam and an inner phaser for the small internal exhaust cam. Controlled either electrically or by oil pressure, it would adjust the intake and exhaust separately. You will notice the small pins in the cam itself, these pins would disengage the internal exhaust cam from the exterior cam by pushing the pin outward so that it can operate and adjust independently. The normal operation position of the pin would be "IN" and oil pressure or electronically (doubt it) would force the pin "OUT" so that the internal cam could spin independently from the exterior cam. Maybe oil pressure that is bled from the VVT phaser into the internal cam tube disengages the cam pin (pushes it up), I don't know for sure... I would have to whip up a few more diagrams before I could say for certain if bleed over could produce enough oil pressure to do that.

As the CiC operates independently, and the engine returns to normal operation, the lack of oil pressure inside the internal cam tube would allow the cam pin to return to the :IN" position, locking the cams together again for normal operation.

I hope this explanation is easy to follow...
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