Reinforced inlet valves HONDA Civic X L15B7

HONDA engines covered

The L15B7 is the Civic X 1.5 litre turbocharged four-cylinder with 16 valves and direct injection. It delivers 170 to 182 hp in the 1.5 VTEC saloons and coupés, and 205 hp in the Civic Si.

Its cylinder head carries 8 inlet valves, two per cylinder. A remap that raises boost pressure, a bigger turbo or track use expose them to more heat and harder impacts.

FERREA reinforced inlet valves

On a turbocharged engine the inlet valve takes the air compressed by the turbo, strikes its seat at every closing and slides continuously in its guide, between 400 and 550 °C. At these temperatures the chrome-silicon steel of conventional valves drops from 500 MPa at 500 °C to 250 MPa at 600 °C, 50 % of its strength lost.

FERREA Competition Plus valves are made from a special alloy: they add 20 % hot and fatigue strength and extend seat life by 25 %.

The F2446P takes the head from 28 to 29 mm with stem and length unchanged: the flow area widens and the cylinder fills better, provided the 8 inlet seats are machined to that diameter.

Inlet valve technical specification

Fitting details

FERREA pairs this engine with its K10116 collets, for a 5.5 mm stem.

The 29 mm F2446P needs inlet seats machined to its size; the 28 mm F2445P fits seats reconditioned to factory size.

Technical guide

The brand offered

Founded in 1978 in Florida, FERREA Racing Components makes its valves from one-piece forged bars, then machines them on CNC equipment. Its parts run in NASCAR, in drag racing and in many tuned engines.

How to choose

Both sets share material, stem and length; only the head diameter changes:

When reinforced valves become necessary

• Higher boost pressure or bigger turbo
• Higher-lift camshafts or stiffer springs
• Raised rev limit
• Cylinder head rebuilt for track use
• Marked or worn original valves

Compatible vehicles

Related products

With the cylinder head off, replace the 8 exhaust valves of the L15B7 as well.