Tomei 1.5mm Oil Gallery Orifice RB26 RB25 RB20

Tomei Oil Gallery Orifice RB26 RB25 RB20

The oil gallery orifice controls the amount of oil flow that is delivered to the head to lubricate the parts in the cylinder head and to cool down the engine assembly. However, the stock oil-gallery orifice has a hole that is too large which allows too much oil to be delivered to the cylinder head. By restricting the diameter of the orifice to φ1.5mm (Normal is φ2.0mm) Tomei has succeeded in securing enough lubrication to the camshaft and valve while maintaining the correct amount of oil in the oil pan which resolved these common problems:

• Too much blow-by gas
• Blowing engine oil
• Leaking oil through the valve guides
• Insufficient oil delivery to the crank journal
• Allows air pockets into the system from when the oil pan is under horizontal G-Forces