S-VT, or Sequential Valve Timing, is an automobile variable valve timing technology developed by Mazda. S-VT varies the timing of the intake valves by using hydraulic pressure to rotate the camshaft. S-VT was introduced in 1998 on the ZL-VE engine and is used in the B-, Z-, MZR- and J-families of engines.^{[citation needed]}

• Variable valve timing