Reinforced exhaust valves Ford Focus Zetec-E 2.0 16V

Ford engines covered

The Zetec-E 2.0 16V, engine codes EDDB, EDDC, EDDD and EDDF, powers the first Focus from 1998 to 2005 as a three and five-door, a saloon and a Turnier estate.

Its cylinder head carries 8 exhaust valves, two per cylinder. SUPERTECH reproduces them with a 6.012 mm stem, a 96.7 mm overall length and a single lock groove, like the original valve; the head is 28 mm at standard size. FERREA offers a 27.96 mm head at standard size or 28.96 mm at +1 mm, with the same stem and a 97.16 mm length.

SUPERTECH and FERREA reinforced exhaust valves

Tasked with letting the burnt gases out, the exhaust valve is the hottest part in the cylinder head. On an unboosted engine like the Zetec-E, its head metal sits between 760 and 870 °C, and exceeds 1,000 °C under a turbo or supercharger. The seat dissipates about 75 % of that heat, the guide nearly 20 %. As temperature climbs, steel gives way: an EV8-family steel, chosen as the reference, copes with 550 MPa at 600 °C and only 300 MPa at 800 °C. Heavier load, higher revs or extra boost drive the temperature up again: once fatigued, the head distorts and then leaks on its seat.

To survive these temperatures, reinforced valves switch material. SUPERTECH offers black nitride stainless steel, whose hardened, smoothed surface cuts stem friction and guide wear, then Inconel, a nickel-based alloy able to retain 860 MPa at 730 °C and 554 MPa near 815 °C, about 85 % above the reference steel around 800 °C: the version to fit on a boosted Zetec. For its Competition Plus valves, FERREA reports 20 % higher hot strength and a seat lasting 25 % longer. Three finishes are therefore available: black nitride stainless and Inconel from SUPERTECH, chromed stem stainless from FERREA.

Two versions enlarge the head: the F1818P by 1 mm, to 28.96 mm, and the FEVI-1038 by 2 mm, to 30 mm. Burnt gases leave the chamber earlier, fresh charge flows in more easily and power benefits. The exhaust seats then have to be machined to the chosen diameter.

Exhaust valve technical specifications

The FEVN-1035-8 and the F1817P are at standard size; the F1818P enlarges the head by 1 mm and the FEVI-1038-8 by 2 mm.

Valve fitting

Both SUPERTECH part numbers keep the original single lock groove: on reassembly, as with the FERREA valves, check that each pair of collets sits properly in the groove.

The FEVN-1035-8 and the F1817P fit on simply reground seats; the F1818P needs exhaust seats machined to 28.96 mm, the FEVI-1038-8 to 30 mm.

Replace the 8 exhaust valve stem seals at the same time and fit valves from the same set.

Technical guide

Our brands

	SUPERTECH, the Silicon Valley specialist, has worked for more than 30 years on racing valves, springs, guides and titanium retainers. Each valve, in stainless, titanium or Inconel, starts from one precise engine and is fine-tuned with seasoned drag racing, rally and circuit tuners.
	FERREA Racing Components, launched in 1978 on the initiative of Daniel Urrutia and Horacio Ferrea, produces its stainless, titanium and nickel alloy valves in its plants in Florida and Argentina. They are found with engine builders in every country, in NASCAR as in drag racing.

How to choose

Clamped by the retainer, the collets hold the valve by its groove; the SUPERTECH valves have just one, like the original. The choice therefore rests on head diameter and material, which decide what you gain from them.

When reinforced valves become necessary

• Increased camshaft lift or firmer valve springs
• Higher cut-out speed
• Zetec converted to boost (Inconel version recommended)
• Cylinder head redone for circuit, rally or hill climb use
• Original exhaust valves burnt, worn or already reground

Vehicle compatibility

OEM part number (exhaust valve):

Don't forget the inlet valves

Zetec-E cylinder head off the engine? Take the chance to replace the inlet valves as well and fit new valve stem seals. Here is the part for this engine: