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Reinforced valve spring kits Nissan RB26DETT

Reinforced valve spring kit Nissan RB26DETT

€753.98 (tax incl.)

€942.48 (tax incl.) -20%

Kits of 24 reinforced valve springs for the Nissan RB26DETT.

Brands: SUPERTECH, FERREA
Engine: RB26DETT (Skyline GT-R R32, R33, R34, Stagea 260RS)
Springs: single or double
Contents: springs, retainers, spring seats and valve locks depending on the kit

SPRK-M1007S-RB

Brand - Type of Springs: SUPERTECH - SPRINGS SINGLE 70 LBS

On order, 15 to 30 days lead time

The Nissan RB26DETT six-cylinder of the Skyline GT-R

The RB26DETT is the 2.6-litre twin-turbo straight six of the Nissan Skyline GT-R R32, R33 and R34 and the Stagea 260RS. With 24 valves operated by mechanical tappets, it takes 24 springs.

Nissan fits spring 13203-05U00 (the only outer spring), retainer 13209-05U00, spring seat 13205-58S00 and valve locks 13210-D4200, identical on R32, R33 and R34.

SUPERTECH and FERREA reinforced valve spring kits

On an RB26, every spring is asked to lower the valve as soon as opening ends, then make it follow the cam until it seats. With big turbos and taller cams, the engine revs far above its stock range; when force falls behind, the valve escapes the profile and may touch the piston.

SUPERTECH offers kits from 276 N (62 lbs) to 409 N (92 lbs) seat pressure, single or double, including one with different inlet and exhaust pressures. FERREA rates KT4052 at 489 N under 39.0 mm and 934 N for 10 mm of lift.

Valve spring kit technical specification

Part number	Brand	Springs	Outer / inner Ø	Seat pressure	Open pressure	Rate	Max lift	Kit contents
SPRK-M1007S-RB	SUPERTECH	Single 70 lbs	Outer 28.1 / 20.0 mm	311 N at 40.7 mm	836 N at 11.0 mm	46.7 N/mm	14.9 mm	24 single springs, 24 retainers, original spring seats kept
SPRK-M1005S-RB	SUPERTECH	Single 62 lbs		276 N at 40.7 mm				24 single springs, 24 retainers, 24 shims, original spring seats kept
SPRK-M1007D-RB-2L	SUPERTECH	Double 92 / 82 lbs	Outer 28.1 / 20.0 mm Inner 20.0 / 15.2 mm	409 N at 40.7 mm (inlet) 365 N at 40.7 mm (exhaust)		55.6 N/mm	14.9 mm	24 double springs, 24 retainers, 24 spring seats
SPRK-TS1015-RB26	SUPERTECH	Double 92 lbs	Outer 27.5 / 20.0 mm Inner 20.0 / 15.2 mm	409 N at 33.0 mm		53.8 N/mm	12.9 mm	24 double springs, 24 retainers, 24 spring seats
KT4052	FERREA	Double	Outer 28.0 / 20.8 mm Inner 20.8 / 16.5 mm	489 N at 39.0 mm	934 N at 10 mm	44.5 N/mm	12.0 mm	24 double springs, 24 retainers, 24 spring seats, 24 valve locks

Valve spring kit fitting details

Part	Nissan original	Reinforced spring kit
Spring	13203-05U00 (outer spring)	Kit specific: SPR-M1005S, SPR-M1007S, SPR-M1007D, SPR-TS1015 (SUPERTECH); S10090 (FERREA)
Retainer	13209-05U00	Kit specific: RET-NRB60/TS (SUPERTECH); E11057 (FERREA)
Spring seat	13205-58S00	Original kept (M1005S, M1007S); kit specific: SEAT-TS1015 and SEAT-TS1015-2, SEAT-RB26/TS9 (SUPERTECH); SL1047 (FERREA)
Collets	13210-D4200	Original kept (SUPERTECH); kit specific: K10072 (FERREA)

SPRK-M1005S-RB and SPRK-M1007S-RB change springs and RET-NRB60/TS retainers and keep the original spring seat, with 24 SS-3025 shims for the former. SPRK-M1007D-RB-2L adds SEAT-TS1015 (inlet) and SEAT-TS1015-2 (exhaust) spring seats, SPRK-TS1015-RB26 adds SEAT-RB26/TS9. FERREA KT4052 gathers S10090 springs, E11057 retainers, SL1047 spring seats and K10072 valve locks.

Valve shut, installed height refers to the room the spring has from one of its seats to the other. SUPERTECH pressures are given at 40.7 mm, or 33.0 mm for SPRK-TS1015-RB26 which changes the spring seat; FERREA states 39.0 mm. Recutting the seats raises this dimension and costs one spring rate per millimetre: check every valve.

	SUPERTECH	FERREA
Installed height	SPRK-M1007S-RB : 40.7 mm SPRK-M1005S-RB : 40.7 mm SPRK-M1007D-RB-2L : 40.7 mm SPRK-TS1015-RB26 : 33.0 mm	39.0 mm
Seat pressure at this height	311 N 276 N 409 N (inlet) / 365 N (exhaust) 409 N	489 N

Technical guide

Our brands

	Operating from San Jose in California, SUPERTECH has won over GT-R tuners with its racing valvetrain. The purified chrome-silicon-vanadium wire of its springs and the inspection of every series by radiography, ultrasound and laser measurement account for its standing.
	Behind FERREA Racing Components stands Horacio Ferrea, born in Argentina and settled in Florida as an engine builder, who launched the brand in 1978. Its workshops turn out springs, retainers, valves and guides, used in drag racing, NASCAR and many race RB26s.

How to choose

With more force, the valve keeps hold of the cam when the turbos blow hard and revs soar: taller cams, a later cut-off or more boost then become possible without valve float. Seat pressures on this page span 276 to 489 N. Stay below the lift each kit tolerates: 12.0 mm at FERREA, 12.9 to 14.9 mm at SUPERTECH. The FERREA kit, the stiffest here, is meant for the most extreme builds.

Criterion	Key point
Choosing the pressure	Within the SUPERTECH part numbers, the lbs figure is the seat force: 62 and 70 lbs for the single kits, close to a reinforced road fitment, 92 lbs for the double kits, with SPRK-M1007D-RB-2L reduced to 82 lbs on the exhaust. FERREA KT4052 targets big turbos with 489 N. Balance lift, target rpm and boost; surplus force needlessly tires cams and mechanical tappets.
Single or double spring	With a single kit, one stiffer spring takes the place of the stock spring. A double kit adds an inner spring, which shares the effort and curbs vibration, plus a specific spring seat to centre it on the head.

When reinforced springs become necessary

Turbos larger than the original T28s
Taller or longer-duration camshafts
Increase in boost pressure
Engine built for circuit, drift or hillclimb
Weakened original springs, valve float noticed on the dyno

Compatible vehicles

Model	Engine code	Years
Nissan Skyline GT-R (R32) 2.6 Twin Turbo 4x4 (BNR32)	RB26DETT	1989-1993
Nissan Skyline GT-R (R33) 2.6 Twin Turbo 4x4 (BCNR33)	RB26DETT	1994-1999
Nissan Skyline GT-R (R34) 2.6 Turbo 4x4 (BNR34)	RB26DETT	1999-2002
Nissan Stagea 260RS (WC34) 2.6 Twin Turbo	RB26DETT	1996-2001

OEM part number (valve spring): 13203-05U00.

Important: these kits only target the RB26DETT of the Skyline GT-R R32, R33 and R34 and the Stagea 260RS; the RB25DET and RB20DET have different heads.