SUPERTECH bronze valve guides Opel Z16LER A18XER

Opel engines concerned

This kit equips the 16-valve cylinder head of two Opel four-cylinders: the Z16LER, the 1.6 litre turbo of the Corsa D OPC and Vauxhall Corsa VXR, also fitted to the Westfield, and the A18XER, the naturally aspirated 1.8 litre of the Astra H and J, Insignia A, Mokka and Zafira B and Tourer.

A single SUPERTECH part number, GDE-OP50, serves both sides: 4.985 mm bore, 36.8 mm length and 10.06 mm outside diameter, oversized by 0.001" (0.025 mm). The kit assembles two sets of 8, i.e. the 16 guides of the cylinder head.

SUPERTECH manganese bronze valve guides

Held in the cylinder head, each guide keeps the valve on the axis of its seat, gives part of the stem's heat to the aluminium and carries the stem seal. When worn, it allows the stem to play: the valve closes crooked, oil reaches the combustion chamber and blue smoke, oil consumption and falling compression follow.

SUPERTECH produces these guides with precision in its copper-based manganese bronze which, by the brand's account, dissipates heat much more efficiently than first-fit sintered parts. These guides generally go with reinforced valves. Two sets of 8 in the kit cover both inlet and exhaust.

Valve guide technical specifications

Valve guide installation

Technical guide

For these engines our catalogue also offers SUPERTECH reinforced valves:

Our brand

Based in California, SUPERTECH has spent more than three decades designing competition valves, retainers, springs and guides. Numerical calculation, ultrasonic, X-ray and laser inspection, testing alongside engine tuners: every part follows this path before going on sale.

Manganese bronze

Copper and zinc, combined with manganese, iron and aluminium, make up this high-strength bronze. It keeps its hardness, wears little under friction and copes well with corrosion, hence its use for bushes and guides under heavy loads.

When valve guides must be replaced

• Oil burnt after running along the stems
• Reinforced valves added to a worn head
• Head reworked for race, drift or rally use
• Complete overhaul of the valve train

Vehicle compatibility

OEM part number (valve guide, Z16LER): 24405805 (standard), 24438044 (repair size)

Remember the valve stem seals

Fresh guides call for fresh stem seals. SUPERTECH lists the VSI-GM50-E seal for this guide; original Opel part number: 24405819.