Reinforced inlet valves HONDA B16A B18C

HONDA engines covered

The B16A and B18C are Honda's 1.6 and 1.8 litre 16-valve VTEC four-cylinder engines, from 150 to 200 hp. They power the Civic IV, V and VI VTi, the CRX II and III, the Capa, the Integra (DA6, DA8, DB7) and the Integra VTiR and Type R coupé (DC2), from 1988 to 2002.

Each engine has 8 Honda 14711-PR3-000 inlet valves (14711-P73-J01 on the B18C6): 33.0 mm head, 5.5 mm stem, held by 14781-PR7-A01 collets (14781-PJ7-003 on the B16A1). Sharper camshafts, stiffer springs or a higher rev limit load them well beyond stock use.

SUPERTECH and FERREA reinforced inlet valves

At high revs the inlet valve lets fresh air in and shuts the port again dozens of times every second. On each cycle its head lands back on the cylinder head seat while its stem moves constantly up and down in the guide. Operating temperature sits between 400 and 550 °C, and the chrome-silicon steel used for Honda's own valves is already weakening in that zone: 500 MPa at 500 °C, then only 250 MPa at 600 °C, just above it, a 50 % drop. Extra lift, firmer springs, more revs or a turbo all add to the impacts, wear and heat the part has to take.

The SUPERTECH valves are forged from a chrome-nickel competition stainless steel close to EV8, which still holds 650 MPa at 500 °C and 550 MPa at 600 °C: 30 % and then 120 % more than the standard steel. Their black nitride finish hardens and smooths the surface, so the stem slides through its guide with less friction. FERREA has three ranges: Competition Plus, a chromed-stem stainless design, rated 20 % stronger in heat and fatigue than ordinary stainless valves, with seats that last 25 % longer; the 6000 Series in EV8 stainless; and the 5000 Series, whose stainless body gets a hard chromed stem.

Both brands also supply +0.5 and +1 mm oversizes: the head grows to 33.5 or 34.0 mm instead of 33.0 mm, with the stem and overall length unchanged. More air flows past the seat, cylinder filling improves and power rises with it, if the inlet seats are machined for the bigger head.

Inlet valve technical specification

FERREA: flat head for F5502*8 and F5503*8.

Dished head for HIVN-1000-8, HIVN-1000D-8 and HIVN-1001-8; flat face head for HIVN-100F-8, HIVN-200F-8, HIVN-1000F-8 and HIVN-1001F-8; HIVN-200F-8 with undercut stem under the head.

Fitting details

The +0.5 mm and +1 mm sizes need inlet seats cut to 33.5 or 34.0 mm, workshop work to plan with the cylinder head rebuild.

Valve clearance is set with screws on the rocker arms: after replacing the valves, check and adjust it (0.15 to 0.19 mm cold on the inlet side for the B16A).

Technical guide

Our brands

	SUPERTECH has designed and built racing valvetrain parts in San Jose, California, for more than thirty years. Every valve is drawn up for one particular head, inspected with ultrasound, X-ray and laser gauging, and then tested alongside race engine builders on drag strips and circuits.
	FERREA Racing Components dates from 1978, when two Argentinian engine builders started it in Fort Lauderdale, Florida; all production stays in house. The one-piece valves start as forged bar stock, are CNC machined throughout and race in NASCAR, at the drag strip and on track.

How to choose

Two points guide the choice: the state of your inlet seats, which sets the size, then the material and finish you want, which points to the brand.

When reinforced valves become necessary

• Sharper camshafts or stiffer valve springs
• Rev limit raised
• Adding a turbocharger or supercharger
• Cylinder head rebuilt for track, hillclimb or rally
• Stock valves damaged, worn or already machined to repair size

Compatible vehicles

OEM part number (inlet valve): 14711-PR3-000; 14711-P73-J01 (B18C6)

Don't forget the exhaust valves

A rebuilt B16A cylinder head also takes new exhaust valves and fresh valve stem seals. You will find these reinforced parts on the following pages: