Reinforced exhaust valves Nissan Skyline Z VR30DDTT

Nissan engines covered

The VR30DDTT is Nissan's 3.0 litre twin-turbo, direct-injection V6 with 24 valves. It powers the Skyline V37 and the new Z, including the NISMO version.

Its two cylinder heads carry 12 exhaust valves. In standard size, the valve offered has a 28.5 mm head, a 5.46 mm stem and a 97.5 mm overall length. The two turbos, mounted close to the heads, expose them to hot, pressurised gases.

FERREA reinforced exhaust valves

On a forced-induction engine the metal of the exhaust head goes beyond 1,000 °C, while a naturally aspirated engine stays between 760 and 870 °C. The seat absorbs about 75 % of the heat, the guide 20 %. An EV8 family exhaust steel is the reference: 550 MPa at 600 °C, 300 MPa at 800 °C. A remap raising boost speeds up head fatigue, distortion and then seat leakage.

The valve offered is made of Super Alloy, a nickel-based alloy, and belongs to the Competition Plus range, which brings 20 % more hot strength and 25 % longer seat life.

The F2412P widens the head to 29.5 mm: the burnt gases are evacuated faster and scavenging improves, with about 10 to 12 cfm of extra flow per millimetre of head. The 12 exhaust seats are then machined to that diameter.

Exhaust valve technical specifications

F2411P is at standard size and F2412P at +1 mm oversize, both in Super Alloy and intended for the Q60.

Valve fitting

Compare the lock groove with the collets you reuse before refitting the springs.

At 28.5 mm the seats are left as they are; with the F2412P, the 12 exhaust seats are cut to 29.5 mm.

Both part numbers have the same 5.46 mm stem and 97.5 mm overall length: the original guides are fine if they are within tolerance.

Technical guide

Our brand

FERREA, founded in 1978, makes its valves in Florida and Argentina. For the VR30DDTT it offers a Super Alloy exhaust valve, in standard size and +1 mm.

How to choose

Same material: the size decides.

When reinforced valves become necessary

• Remap with increased boost
• Larger turbos
• E85 fuel or high power
• Track days
• Cylinder head rebuild with marked exhaust valves

Vehicle compatibility

OEM part number (exhaust valve): 13202-5CA0A

Don't forget the inlet valves

With the heads of a VR30DDTT off, it is the time to replace the inlet valves and the valve stem seals as well.