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Reinforced valve spring kit Nissan GT-R VR38DETT

€1,065.21 (tax incl.)

€1,331.51 (tax incl.) -20%

Kits of 24 uprated valve springs for the Nissan VR38DETT engine of the GT-R (R35).

Brands: FERREA, SUPERTECH
Engine: VR38DETT (GT-R R35)
Springs: double, single or beehive depending on the kit
Contents: springs, titanium upper retainers, lower spring seats depending on the kit

SPRK-TS1012-GTR

Brand - Type of Springs: SUPERTECH - SPRINGS DOUBLE 62 LBS

On order, 15 to 30 days lead time

The Nissan engine covered

These kits are made for the VR38DETT, the 3.8-litre twin-turbo V6 with 24 valves fitted to the Nissan GT-R (R35), built since 2007. Each cylinder has four valves, operated by four overhead camshafts.

Five kits are offered: two from FERREA, with double or single springs, and three from SUPERTECH, with double springs of 62 and 66 lbs or beehive springs of 78 lbs. Each kit replaces the original springs.

FERREA and SUPERTECH reinforced valve spring kits

Once the lobe moves away, the spring has to bring the valve back onto its seat without delay. If the engine revs too high for the spring rate, the valve loses contact with the cam, bounces and sometimes strikes the piston, which builders call valve float.

The five kits differ in seat pressure, spring rate and maximum lift, all given in the table. FERREA states 90 lbs at the seat for both of its kits; SUPERTECH ranges from 62 to 78 lbs, at installed heights between 34.6 and 35.65 mm. One kit fits a whole engine.

Valve spring kit technical specification

Part number	Brand	Springs	Outer / inner Ø	Seat pressure	Open pressure	Rate	Max lift	Kit contents
KT4015	FERREA	Double	Outer 28.0 / 20.8 mm Inner 20.8 / 15.9 mm	90 lbs at 37.5 mm (intake) 90 lbs at 34.35 mm (exhaust)	212 lbs at 27.5 mm (intake) 212 lbs at 24.35 mm (exhaust)	309.6 lbs/in	13 mm (intake) 13.5 mm (exhaust)	24 double springs S10136, 24 titanium upper retainers E11106, 12 lower spring seats SL1115 and 12 SL1118, 24 sets of K10102 collets
KT4016	FERREA	Single	Outer 25.2 mm Inner 18.3 mm	90 lbs at 35 mm	160 lbs at 25 mm	177 lbs/in	11 mm	24 single springs S10137, 12 titanium upper retainers E11107 and 12 E11110, 24 lower spring seats SL1116, 24 sets of K10102 collets
SPRK-TS1012-GTR	SUPERTECH	Double 62 lbs	Outer 27.5 / 20.0 mm Inner 20.0 / 15.2 mm	62 lbs at 35.65 mm	162 lbs at 10 mm	10.5 lbs/mm	15.65 mm	24 springs SPR-TS1012, 24 titanium upper retainers RET-TS5.5/T9F, 12 lower spring seats SEAT-TS/GTR-2 and 12 SEAT-TS/GTR
SPRK-TS1012-GTR-BE	SUPERTECH	Beehive 78 lbs	Outer 27.7 / 19.7 mm Inner 23.2 / 15.2 mm	78 lbs at 34.6 mm	178 lbs at 10 mm	10.4 lbs/mm	11.5 mm	24 springs SPR-TS1012-BE, 24 titanium upper retainers RET-TS5.5/T9F-BE, 12 lower spring seats SEAT-TS/GTR-4 and 12 SEAT-TS/GTR-3
SPRK-TS1015-GTR	SUPERTECH	Double 66 lbs	Outer 27.5 / 20.0 mm Inner 20.0 / 15.2 mm	66 lbs at 35.65 mm	187 lbs at 10 mm	12.1 lbs/mm	14.95 mm	24 springs SPR-TS1015, 24 titanium upper retainers RET-TS5.5/T9F, 12 lower spring seats SEAT-TS/GTR and 12 SEAT-TS/GTR-2

Valve spring kit fitting details

Part	Nissan original	Reinforced spring kit
Spring	13203-JF00A (inlet) 13203-JF00C (exhaust)	KT4015 : S10136 KT4016 : S10137 SPRK-TS1012-GTR : SPR-TS1012 SPRK-TS1012-GTR-BE : SPR-TS1012-BE SPRK-TS1015-GTR : SPR-TS1015
Retainer	13209-AC700	KT4015 : E11106 KT4016 : E11107 (inlet), E11110 (exhaust) SPRK-TS1012-GTR : RET-TS5.5/T9F SPRK-TS1012-GTR-BE : RET-TS5.5/T9F-BE SPRK-TS1015-GTR : RET-TS5.5/T9F
Spring seat	13205-53Y00	KT4015 : SL1115 (inlet), SL1118 (exhaust) KT4016 : SL1116 SPRK-TS1012-GTR : SEAT-TS/GTR-2, SEAT-TS/GTR SPRK-TS1012-GTR-BE : SEAT-TS/GTR-4, SEAT-TS/GTR-3 SPRK-TS1015-GTR : SEAT-TS/GTR, SEAT-TS/GTR-2
Collets	13210-53Y00	KT4015, KT4016 : K10102 SUPERTECH : not supplied

The FERREA kits contain 24 springs, 24 titanium upper retainers, the lower spring seats and 24 sets of K10102 collets. The KT4015 pairs the E11106 retainers with SL1115 lower seats on the inlet side and SL1118 on the exhaust side. The KT4016 supplies two upper retainer profiles, E11107 for the inlet and E11110 for the exhaust, with 24 SL1116 lower seats.

The SUPERTECH kits bring together 24 springs, 24 titanium upper retainers and 24 lower spring seats, 12 of each part number. The collets are not included in these kits.

Measure the installed height with the valve closed, between the lower and upper faces of the spring. Each kit states its pressure at its own height, as the table shows: KT4015 at 37.5 mm (inlet) and 34.35 mm (exhaust), KT4016 at 35 mm. Skimming or regrinding lengthens it, and each millimetre gained removes the spring rate from the load. Measure all 24 valves first.

	FERREA	SUPERTECH
Installed height	KT4015 : 37.5 mm (intake), 34.35 mm (exhaust) KT4016 : 35 mm	SPRK-TS1012-GTR : 35.65 mm SPRK-TS1012-GTR-BE : 34.6 mm SPRK-TS1015-GTR : 35.65 mm
Seat pressure at this height	90 lbs 90 lbs	62 lbs 78 lbs 66 lbs

Technical guide

Our brands

	FERREA Racing Components began in Florida in 1978, when the Argentine engine builders Daniel Urrutia and Horacio Ferrea teamed up. The firm makes its own valves, springs, tappets and rocker arms, which compete in NASCAR, drag racing and circuit events.
	SUPERTECH is a California company based in San Jose. For more than thirty years it has designed valve train parts for competition. Its springs, coiled from chrome-silicon-vanadium wire, go through batch checks by X-ray, ultrasound and laser before shipping.

How to choose

Stiffer springs allow higher revs, a more aggressive camshaft or more boost without valve float. The seat pressure runs from 62 to 90 lbs depending on the kit. A higher pressure also wears cams and tappets faster: choose the right value. Before ordering, check that the lift of your camshaft stays below that of the kit, from 11 to 15.65 mm depending on the part number. The seat pressure keeps the valve closed, while the pressure at lift holds it when the cam opens it fully.

Criterion	Key point
Choosing the pressure	Each pressure is given for the installed height of its kit. Consider the cam lift, the target revs and the turbo pressure before aiming for the top of the range: needless pressure tires the valve train and gains nothing.
Single, double or beehive spring	Two concentric springs split the effort and dampen one another: this is the principle of the double kits. The beehive spring is conical and narrows toward the upper retainer: its moving mass is lower, which helps it follow the valve at high revs. The single spring, lighter, suits less extreme use. The choice depends on use and budget, not on performance alone.

When reinforced springs become necessary

A camshaft whose lift exceeds the original
A rev limit raised well beyond standard
Larger turbos or higher boost
An engine built for track or competition use
Worn original springs, valves that float

Compatible vehicles

Model	Engine code	Power	Years
Nissan GT-R (R35) 3.8 V6	VR38DETT	480 to 608 hp	From 2007
Nissan GT-R (R35) 3.8 NISMO	VR38DETT	600 hp	From 2014

OEM part numbers (valve spring, VR38DETT): 13203-JF00A (inlet), 13203-JF00C (exhaust)

Important: these kits are for the VR38DETT of the Nissan GT-R (R35). One kit of 24 fits a complete engine. According to FERREA, the 2009 and 2010 GT-R are covered: for any other year, check the dimensions before ordering.