FERREA bronze inlet valve guides Nissan Infiniti VR30DDTT

Nissan and Infiniti engines concerned

This kit is intended for the inlet side of the cylinder heads of the 3.0 litre twin-turbo Nissan VR30DDTT V6, fitted to the Infiniti Q50 and Q60, the Nissan Skyline V37 and the Nissan Z.

Nissan specifies a finished bore of 5.500 to 5.518 mm and a standard outside diameter of 9.523 to 9.534 mm for these guides. The two heads have 12 inlet valves: the kit supplies 12 guides.

FERREA copper bronze inlet valve guides

On the inlet side, the guide keeps the valve centred over its seat, sends part of the heat taken up by the stem back into the head and supports the seal. When worn, it allows the valve to drift and seat at an angle; oil seeps down the stem, with blue smoke, oil consumption and dropping compression, faults that matter on a turbocharged engine.

FERREA makes these guides from a copper and bronze alloy of American origin that undergoes the brand's own heat treatment, which according to its catalogue helps heat dissipation, wear resistance, high temperature strength and lubrication. Precise CNC machining allows titanium as well as stainless steel valves. Each kit holds the 12 VR30DDTT inlet guides.

Valve guide technical specifications

Valve guide installation

Technical guide

For the VR30DDTT, reinforced valves are available on the inlet and exhaust side:

Our brand

In Florida since 1978, FERREA machines valves, springs, retainers and guides in the USA and Argentina, covering most production engines built up for racing.

When valve guides must be replaced

• Oil passing down the inlet valve stems
• Reinforced valves planned for a tired head
• Cylinder head rebuilt for circuit, drift or rally driving
• Complete valvetrain rebuild

Vehicle compatibility

OEM part number (valve guide): 13212-4HK6A

Remember the exhaust guides

A cylinder head rebuild generally covers inlet and exhaust. For the VR30DDTT we also offer: