Inlet valve guides Subaru EJ20 EJ25 turbo

Applicable Subaru engines

This set fits the inlet side of the Subaru EJ20 and EJ25 turbo flat-four engines: EJ205, EJ207, EJ20G, EJ20U, EJ20X, EJ20Y, EJ255, EJ257 and EJ25DET. They sit under the bonnet of the Impreza, WRX, Forester, Legacy, Outback and Baja.

Each cylinder head has 8 inlet valves, every one guided by a part pressed into the aluminium. Subaru lists this guide as 13212-AA130: 39.5 mm long, 11.1 mm outside diameter and a 6 mm valve stem.

FERREA and SUPERTECH inlet valve guides

In these flat-fours, each inlet valve stem moves inside a guide that keeps it square to the seat, draws off part of its heat and supports the stem seal. Clearance builds up with mileage: the valve tilts, seats badly, oil creeps down the stem, and the driver notices blue smoke, regular top-ups and weaker compression.

FERREA's catalogue describes a copper-based bronze of American origin, which an in-house heat treatment is said to make better at shedding heat, standing up to high temperatures, resisting wear and lubricating the stem. CNC machining holds the tolerances, and titanium and stainless valves are both accepted. SUPERTECH picks a manganese bronze whose heat conduction clearly exceeds, the brand claims, that of sintered guides fitted from new. Eight guides per set, enough for the whole inlet side of a head; they are usually matched with reinforced valves.

Valve guide technical specifications

Valve guide installation

Technical guide

Our brands

	Fort Lauderdale, 1978: FERREA starts there. Today it makes the valve train parts of racing engines, from valves to stem seals, in Florida and in Argentina.
	In California, near San Jose, SUPERTECH has spent thirty years and more designing racing valve train parts: valves, titanium retainers, springs, guides, validated by finite elements and by engine builders.

Standard or oversize?

FERREA supplies standard guides and a 0.025 mm (0.001") oversize. SUPERTECH offers the oversize only, 11.08 mm outside diameter.

Manganese bronze

This bronze combines copper with manganese, aluminium, iron and a little zinc. Tough against continuous sliding and corrosion alike, it goes into heavily loaded bushes, which explains its place here: the metal rubs against the stem on every cycle.

When valve guides must be replaced

• Oil creeping down the stems of the inlet valves
• Reinforced valves destined for a cylinder head with some miles
• Racing cylinder head due for a rebuild
• Valve train brought back to as new

Vehicle compatibility

OEM reference (inlet valve guide): 13212-AA130

Important: FERREA lists these guides for the EJ20 engines of the Impreza WRX and STI 2001-2008. For the EJ25 turbo, only SUPERTECH guides are offered.

Remember the exhaust guides and valve stem seals

After new guides, fit new stem seals as well: FERREA VS1016 for the inlet, per its catalogue.