Reinforced inlet valves FORD 2.3 EcoBoost YVDA N3DA N3DB C23HD0D N38H N48H

FORD engines covered

The 2.3 EcoBoost is a turbocharged 2.3 litre Ford inline four with 16 valves and twin overhead camshafts. It powers the third generation Focus RS (YVDA, 350 hp, 2015 to 2018), the fourth generation Focus ST hatchback and estate (N3DA, N3DB, 280 hp, 2019 to 2025) and the Mustang since 2014 (C23HD0D, N38H, N48H, 269 to 330 hp).

This engine has 8 inlet valves with a 5.47 mm stem. Higher boost pressure, a remap or a bigger turbo subject them to temperatures and impacts well above those of standard use.

SUPERTECH and FERREA reinforced inlet valves

On every cycle the inlet valve lifts to let in the air compressed by the turbo, drops back onto its seat and slides in its guide, several dozen times per second at high revs. It works between 400 and 550 °C; the chrome-silicon steel of a standard valve drops from 500 MPa of strength at 500 °C to 250 MPa at 600 °C, 50 % less.

The SUPERTECH valves are cut from EV8 stainless steel, black nitrided to harden the stem, with a stem thinned under the head and a back cut that clear the air path, and a single groove; EV8 keeps 650 MPa at 500 °C and 550 MPa at 600 °C, 30 % then 120 % more than the original steel. The FERREA Competition Plus valves, stainless with a chrome stem, gain 20 % in hot strength and fatigue resistance, and the seat lasts 25 % longer.

Besides the standard size (32.5 mm head), FERREA offers a +0.5 mm size (33 mm) and SUPERTECH a +1 mm size (33.5 mm). A wider head opens a larger passage at the seat: the cylinder fills better and the engine gains power, provided the 8 inlet seats are cut to the head diameter.

Inlet valve technical specification

F2374P*8 and F2375P*8: Mustang 2.3 EcoBoost (C23HD0D, N38H, N48H) only.

FERREA valves: 4 mm stem tip.

Fitting details

The +0.5 mm and +1 mm sizes require inlet seats cut to 33 mm or 33.5 mm; at standard size the seats keep their diameter.

The SUPERTECH valves are 103.3 mm long and the FERREA valves 103.55 mm.

Technical guide

Our brands

	From its workshop in San Jose, California, SUPERTECH Performance has been producing valves, springs and retainers for racing for more than thirty years. Parts are inspected by ultrasound, X-ray and laser, and each model is engineered for a specific cylinder head with engine builders.
	Two engine builders who came from Argentina founded FERREA Racing Components in 1978 in Fort Lauderdale, Florida. The brand forges each of its valves in one piece from bar stock, then machines it entirely on CNC equipment; its parts race in NASCAR and drag racing.

How to choose

The groove is the recess cut near the end of the stem, where the collets hold the retainer; on this engine you choose the size first, then the brand.

When reinforced valves become necessary

• Higher boost pressure or remap
• Bigger turbo or sharper camshafts
• Higher rev limit
• Cylinder head rebuilt for circuit, rally or drift
• Worn original valves or seats already reground

Compatible vehicles

Related products

For a rebuilt 2.3 EcoBoost cylinder head, the reinforced exhaust valves for the Mustang are on this page: