Reinforced valve spring kit Honda B16A1 B16A3 B17A1 B18C1 B18C2 B18C3

€1,394.75 (tax incl.)

Kit of 16 reinforced valve springs for the Honda B16A1, B16A3, B17A1, B18C1, B18C2 and B18C3 engines.

Brand: FERREA
Engines: B16A1, B16A3, B17A1, B18C1, B18C2, B18C3
Springs: double
Contents: springs, titanium upper retainers, lower spring seats, collets

The Honda engines covered

These kits are meant for Honda's B-family four-cylinders, 16 valves and twin overhead cams: the 1.6-litre B16A1 and B16A3, the 1.7-litre B17A1, then the 1.8-litre B18C1, B18C2 and B18C3. You find them under the bonnet of Civic IV, CRX and Integra models, 1988 to 2001.

In series form, each intake valve carries two concentric springs and each exhaust valve a single one; part numbers vary with the engine code. A retainer caps the spring and collets lock the stem. The FERREA kits replace the whole spring and retainer stack.

FERREA reinforced valve spring kit

At high revs the spring must press the valve back on the cam with no dead time. Otherwise the valve floats, slaps its seat and sometimes meets the piston.

The KT4001 quotes 356 N on the seat and the KT4027 400 N, at 34.0 mm; at 56.9 N/mm the KT4002 is the stiffest. FERREA states its titanium retainers weigh 40 % less than steel.

Valve spring kit technical specification

Part number	Brand	Springs	Outer / inner Ø	Seat pressure	Open pressure	Rate	Max lift	Kit contents
KT4001	FERREA	Double	Ext. 30.5 / 22.9 mm Int. 22.9 / 17.5 mm	356 N at 34.0 mm	845 N at 10.0 mm	48.9 N/mm	14.0 mm	16 springs, 16 titanium upper retainers, 16 lower spring seats, 16 collets
KT4002	FERREA	Double	Ext. 30.1 / 22.8 mm Int. 22.9 / 17.2 mm			56.9 N/mm	13.5 mm	16 springs, 16 titanium upper retainers, 16 lower spring seats, 16 collets
KT4027	FERREA	Double	Ext. 30.0 / 23.1 mm Int. 23.1 / 17.2 mm	400 N at 34.0 mm	934 N at 10.0 mm	51.7 N/mm	14.0 mm	16 springs, 16 titanium upper retainers, 16 lower spring seats, 16 collets

Valve spring kit fitting details

Part	Honda original	Reinforced spring kit
Spring		Kit specific: S10070 (KT4001), S10027 (KT4002), S10104 (KT4027)
Retainer	14765-PW0-000 (B16A1) / 14765-P30-000 (B16A3, B18C3)	Kit specific: E11000 (titanium)
Spring seat	14775-PR3-000	Kit specific: SL1000 (KT4001, KT4027), SL1198 (KT4002)
Collets	14781-PR7-A01 / 14781-PJ7-003 (B16A1)	Kit specific: K10034

Each FERREA kit contains 16 double springs, 16 titanium upper retainers E11000, 16 lower spring seats and 16 collets K10034. These springs require the FERREA parts, so the stock lower spring seat stays out.

Installed height is measured with the valve closed, from the lower spring seat to the upper retainer. The KT4001 and KT4027 are calibrated at 34.0 mm, the figure at which they deliver 356 N and 400 N. A recut seat or a skimmed head lengthens that figure, and the load falls by the spring rate times each millimetre gained. The reference value is repeated below.

	FERREA
Installed height	34.0 mm
Seat pressure at this height	356 / 400 N

Technical guide

Our brands

FERREA appeared in 1978 in Florida, at the initiative of engine builders of Argentine origin. The company makes its own springs, valves, retainers, collets, guides and tappets; NASCAR, dragsters and circuit single-seaters are among its buyers.

How to choose

The firmer the spring, the further valve float is pushed back: higher revs, a livelier cam or forced induction become possible. All three kits fit the whole B family listed here. Measure your camshaft lift first: it must never exceed the kit's maximum lift, 14.0 mm for the KT4001 and KT4027 and 13.5 mm for the KT4002. A lightly modified engine can do without the stiffest spring, which wears cams and tappets faster. Once fitted, check the valve clearance: on the B16 and B18C it is adjusted by screws on the rocker arms.

Criterion	Key point
Which spring to pick	Only the spring separates the three kits: S10070 'endurance' (KT4001), S10027 'high pressure' (KT4002), S10104 'PAC' (KT4027). As the rate climbs, so does the work asked of the camshaft and tappets; keep the value that is enough for your revs and your cam, and no more.
Single or double spring	A double spring pairs two coils of different diameters that nest and damp one another as they vibrate, hence better behaviour at high revs than a lone spring. The titanium upper retainers, the lower spring seats and the collets arrive with the springs.

When reinforced springs become necessary

A livelier camshaft than the original
Maximum revs taken clearly above stock
Turbo or supercharger fitted to a B-family block
Head reworked for circuit, drift or rally
Worn springs, or valves floating at high revs

Compatible vehicles

Model	Engine code	Power	Years
Civic IV 1.6 i 16V VTEC (EE9)	B16A1	150 hp	1989-1991
Civic IV 1.6 4x4 (ED)	B16A1	150 hp	1988-1991
CRX II 1.6 i 16V VTEC (EE8)	B16A1	150 hp	1989-1992
CRX III 1.6 i VTi (EG2)	B16A3	160 hp	1992-1998
Integra 1.8 (DB7)	B18C3	200 hp	1993-2001
Integra Coupé 1.8 VTiR (DC2)	B18C1 / B18C2	170-173 hp	1993-1999
Integra Coupé 1.8 Type R (DC2)	B18C1	200 hp	1993-2001
Acura Integra GSR 1.7	B17A1		1992-1993

Important: these kits cover the B16A1, B16A3, B17A1, B18C1, B18C2 and B18C3 in the manufacturer's list. The B16A2, B18C4, B18C6 and B18C7 are not listed and are not covered here.