BBK Performance Parts - 1996-2004 Ford Mustang GT - Adjustable Vari-time Timing Unit This BBK Vari Time adjustable timer is a great way to maximize horsepower and torque potential on any 4.6L or 5.4L Ford. This BBK Timing Adjuster Will Allow for easy + or – 10 Degrees advance or retard timing. Simple to install, Plus It's a great looking CNC machined component. Recommended for all Nitrous and Supercharged applications.