Timing your MZR or Duratec engine isn't like the older MX-5's. These engines are what's known as "keyless" timing systems. That means as soon as the hardware is loose on your crank or cam gears, the timing must be held in place with these, highly accurate specialty tools. This will lock your Crankshaft an Camshafts in place! 

Compatibility: 

• All 2.0,2.3,2.5L MZR and Duratec Engines

Does NOT work on the 2.0L Automatics or the M8 equipped blocks.