Reinforced exhaust valves Toyota Land Cruiser 200 4.7 V8 2UZ-FE

Toyota engines covered

The 2UZ-FE is Toyota's 4.7 litre, 32-valve V8 with VVT-i variable valve timing that powers the Land Cruiser 200 (UZJ200) from 2007.

It has 16 exhaust valves, original part number 13715-50070 (superseding 13715-50060), with a 5.465 to 5.480 mm stem. In a heavy off-roader that tows or runs loaded, they stay hot for long periods in contact with burnt gases.

SUPERTECH reinforced exhaust valves

The metal of an exhaust valve head reaches 760 to 870 °C on a naturally aspirated engine and passes 1,000 °C with forced induction. The seat removes about 75 % of that heat and the guide about 20 %. An EV8 family steel keeps 550 MPa at 600 °C, but only 300 MPa at 800 °C: the head fatigues, distorts and the seat loses its seal.

The TEVI-1093D-16 is made of Inconel, a nickel-based superalloy: 860 MPa at 730 °C and 554 MPa at 815 °C, roughly 85 % better than EV8 steel around 800 °C. Its head is dished.

Its head measures 30.5 mm, 1.5 mm more than the standard size: burnt gases leave the cylinder faster, to the benefit of filling. The 16 exhaust seats are machined to this size.

Exhaust valve technical specifications

TEVI-1093D: 30.5 mm dished head (+1.5 mm), 5.47 mm stem, 95.1 mm length, Inconel.

Valve fitting

When refitting, check that the 90913-03028 collets sit properly in the stem groove.

Have the 16 exhaust seats machined for the 30.5 mm head before fitting.

Fit all 16 valves from the same set and change the exhaust valve stem seals at the same time.

Technical guide

Our brand

SUPERTECH Performance, based in California, has been designing racing valves and valvetrain parts for more than thirty years. For the 2UZ-FE VVT-i V8, it offers a dished-head Inconel exhaust valve, +1.5 mm oversize.

How to choose

Only one version exists for this engine:

When reinforced valves become necessary

• Adding a supercharger or a turbo (Inconel version recommended)
• Heavy towing or intensive off-road use
• Higher lift camshafts
• Cylinder head rebuild with burnt exhaust valves

Vehicle compatibility

OEM part number (exhaust valve): 13715-50070 (supersedes 13715-50060)

Don't forget the inlet valves

With both 2UZ-FE cylinder heads off, replace the inlet valves and the valve stem seals too.