Subaru EZ30 Master Timing & Water Pump Service KitThe Definitive "Engine Out" Solution for the H6 Platform. The Subaru EZ30 3. 0L Flat 6 is a masterpiece of engineering, but it is notoriously unforgiving when it comes to timing maintenance. Unlike the simpler EJ series, the EZ30 utilizes a complex dual chain system that relies on perfect oil pressure and tensioner integrity. By the time you hear the "H6 rattle" on a cold start, the damage to your guides is likely already done. The Roo Racing Master