Recently installed a Procharger on the car and had it tuned. During the tune we had issues with cam angle causing knock. After checking the datalogs we found the cams were doing as the tune commanded up 'til about 4200 rpm. At that point the tune calls for 2.5* cam angle, but the logs show they're swinging from 0* to ~17*. The tuner tried several things to see if the VCT would respond differently, like basing them on load only and then assumed torqued only. Neither affected them differently, they still swing straight to 17*. It's not a smooth transition either, just 0* then hard pitch to 17*. He finally commanded the whole VCT table for WOT loads to 0* and the VCT sat there and we made a clean pass. Unfortunately my power curve falls short because of this and only has about 15* of spark in it in case VCT decides to just do what it wants. Power is falling off at 5250rpm with the cams locked at 0*.
I do have Comp phaser limiters in the phasers and these are stock cams, stock valve springs on max 9psi. So 20* is the max. I have a feeling the phaser springs have gone bad or something, only thing I can think to cause them to go full tilt. Not getting any CEL's and I've put 120 miles on the car since the dyno.
The car feels sluggish during normal driving. He left the VCT table stock for normal driving loads so it should do whatever stock commands. Off the pedal at a stop the cams sit at ~0*. As soon as I give it pedal and start to roll through gears the cams go right to 17* (via livewire monitor "actual cam angle" and "right bank cam angle"). I've done a rolling load test to see if there's any transition difference from the cam angle values to avail. In 4th gear starting at .30 load I roll the pedal down to .40 load, .50, .60. All through the load transition the cam angle remains the same, ~17*. At about .60 load the pedal is down far enough that the BOV wants to close and boost up so the cams instantly roll back to 0*. Could this by why the car feels like it's lost it's spunk during normal driving? Phasers gone bad?
I do have Comp phaser limiters in the phasers and these are stock cams, stock valve springs on max 9psi. So 20* is the max. I have a feeling the phaser springs have gone bad or something, only thing I can think to cause them to go full tilt. Not getting any CEL's and I've put 120 miles on the car since the dyno.
The car feels sluggish during normal driving. He left the VCT table stock for normal driving loads so it should do whatever stock commands. Off the pedal at a stop the cams sit at ~0*. As soon as I give it pedal and start to roll through gears the cams go right to 17* (via livewire monitor "actual cam angle" and "right bank cam angle"). I've done a rolling load test to see if there's any transition difference from the cam angle values to avail. In 4th gear starting at .30 load I roll the pedal down to .40 load, .50, .60. All through the load transition the cam angle remains the same, ~17*. At about .60 load the pedal is down far enough that the BOV wants to close and boost up so the cams instantly roll back to 0*. Could this by why the car feels like it's lost it's spunk during normal driving? Phasers gone bad?
