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Reinforced valve spring kits Mitsubishi 4G63 naturally aspirated

Reinforced valve spring kit Mitsubishi 4G63 naturally aspirated

€504.41 (tax incl.)

€630.52 (tax incl.) -20%

Reinforced valve spring kits for the naturally aspirated Mitsubishi 4G63.

Brands: SUPERTECH
Engines: 4G63 naturally aspirated, 8 and 16 valves
Springs: beehive, double or single
Contents: springs, retainers and spring seats, depending on the kit

SPRK-M1007S

Brand - Type of Springs: SUPERTECH - SPRINGS SINGLE 78 LBS

On order, 15 to 30 days lead time

The naturally aspirated Mitsubishi 4G63 engine

The 4G63 is Mitsubishi's 2.0-litre inline four-cylinder. This page covers its naturally aspirated versions, with 8 or 16 valves and one spring per valve; the turbocharged 4G63T has a page of its own.

The kits below replace the original springs and their upper retainers. They come in three families, beehive, double and single springs, to suit lighter or more demanding builds.

SUPERTECH reinforced valve spring kits

As soon as the cam lobe has gone, the spring must send the valve straight back to its seat; if it is too weak for the revs, the valve floats and can hit the piston.

Here the SPRK-M1007S gives 347 N at the seat, the SPRK-M1007D 409 N, the SPRK-M1007BE-1 356 N and the SPRK-M1007BE-2 423 N, at their own installed heights.

Valve spring kit technical specification

Part number	Brand	Springs	Outer / inner Ø	Seat pressure	Rate	Kit contents
SPRK-M1007S	SUPERTECH	Single 78 lbs	Outer 28.1 mm Inner 20.0 mm	347 N at 39.6 mm	46.6 N/mm	Single springs, RET-M65/T1 retainers
SPRK-M1007D	SUPERTECH	Double 92 lbs	Outer 28.1 / 20.0 mm Inner 20.0 / 15.2 mm	409 N at 39.6 mm		Double springs, RET-M65/T1 retainers, SEAT-M1007D spring seats, VS-H6.6E
SPRK-M1007BE-1	SUPERTECH	Beehive 80 lbs		356 N at 38.6 mm		Springs, RET-M65TBE retainers, SEAT-M65BE-1 spring seats
SPRK-M1007BE-2	SUPERTECH	Beehive 95 lbs		423 N at 37.2 mm		Springs, RET-M65TBE retainers, SEAT-M65BE-2 spring seats

Valve spring kit fitting details

Part	Mitsubishi original	Reinforced spring kit
Spring		Kit specific: SPR-HM1007BE (SPRK-M1007BE-1 and -2), SPR-M1007D (SPRK-M1007D) or SPR-M1007S (SPRK-M1007S)
Retainer		Kit specific: RET-M65TBE (beehive kits) or RET-M65/T1 (double and single kits)
Spring seat		Kit specific: SEAT-M65BE-1, SEAT-M65BE-2 or SEAT-M1007D; no spring seat with the SPRK-M1007S
Collets		Original kept

Each kit pairs its springs with specific upper retainers: RET-M65TBE for the beehive kits, RET-M65/T1 for the double and single kits. The beehive kits come with SEAT-M65BE-1 or SEAT-M65BE-2 spring seats, the double kit with a SEAT-M1007D spring seat. Split collets are not part of the contents: the original ones stay in place. The number of pieces per kit is not shown on this page, so please ask us to confirm it before ordering.

The installed height is read with the valve closed, between the two spring seats. SUPERTECH quotes the pressures of these kits at 38.6 mm, 37.2 mm or 39.6 mm, depending on the part number. Seat grinding or head skimming raises that figure, and the pressure then falls by the spring rate per millimetre gained: measure each valve before closing up the engine.

	SUPERTECH
Installed height	SPRK-M1007S : 39.6 mm SPRK-M1007D : 39.6 mm SPRK-M1007BE-1 : 38.6 mm SPRK-M1007BE-2 : 37.2 mm
Seat pressure at this height	347 N 409 N 356 N 423 N

Technical guide

Our brands

SUPERTECH, a California company based in San Jose, has designed valve train components for racing for over thirty years. Springs made of chrome-silicon-vanadium wire are tested batch after batch with X-ray, ultrasound and laser checks before they leave the warehouse.

How to choose

The higher the pressure, the better the valve stays against the cam at high revs, which allows a livelier camshaft without float. On this page the seat pressure runs from 347 to 423 N. Make sure your camshaft lift stays within what the chosen spring accepts before you order.

Criterion

Key point

Choosing the pressure

In each part number, 80, 95, 92 and 78 are the seat pressure in pounds, i.e. 356 N, 423 N, 409 N and 347 N for the SPRK-M1007BE-1, SPRK-M1007BE-2, SPRK-M1007D and SPRK-M1007S. Reason from the camshaft lift and the intended use rather than aiming for the maximum: an excessive pressure tires the cams, the followers and the timing drive. Only the SPRK-M1007S states a rate, 46.6 N/mm; none is given for the other kits.

Beehive, double or single spring

A beehive spring is conical and narrows toward the retainer: the moving mass drops and a lighter retainer follows acceleration better. A double spring nests two concentric springs, the inner one reinforcing and damping the outer. A single spring is simpler and suits moderate builds.

When reinforced springs become necessary

A camshaft sharper than the original
An engine used on track or in competition
A reworked head or lightened valves
Engine speed above the standard setup
Tired springs, valves floating earlier than before

Compatible vehicles

Model	Engine code	Power	Years
F	R
E	N
N	L
I	T
E	S
D	E

Important: these kits are for the naturally aspirated Mitsubishi 4G63, in its 8-valve and 16-valve versions. The turbocharged 4G63T, the 4G15 and other Mitsubishi engines are covered elsewhere or not at all. Confirm the piece count and your cylinder head version before ordering.