I noticed an improvement in throttle response with a DV+ too, but I'm also getting compressor stall with it (the 'cha cha cha cha' noise when closing the throttle), which suggests to me the flow through the DV+ is inadequate, or it's not reactive enough in mapped cars. Mine's standard bar the DV+ and remap. I might try reoiling the piston, but I would have thought the PCV would keep it lubed.