GSC P-D Mitsubishi 4G63T Beehive Valve Springs & Ti Retainer Kit

GSC Power-Division Beehive Valve Spring Kit with Titanium Retainers — 4G63 (5041)

A high-pressure beehive spring package for the 4G63, and the reason to spec it over a conventional round-wire spring comes down to the coil geometry.

Beehive springs allow for a smaller, lighter retainer, which reduces reciprocating valvetrain mass and gives more valve control at high RPM. The tapered coil diameter also greatly reduces coil spring surge — the harmonic that causes float — and improves valve control at extreme RPM levels.

The spring is made with an ovate wire using advanced material heat treatment methods for superior load loss capability. That means the highest level of spring load retention while maintaining good fatigue life across the life of the spring. Nano peened for faster break-in and less spring stress. Every batch is scrutinized for tensile strength, ductility, inclusion content, and fatigue toughness, and each new design is tested to 9,000 rpm.

Rated to 10,500 rpm with cams up to 12.1mm net lift — the ceiling is seal-to-retainer contact, not the spring.

Spring pressures: intake 100 lbs at 1.539" install height, exhaust 107 lbs at 1.519". Open pressures are 250 lbs at 1.078" intake and 256 lbs at 1.058" exhaust. Uses the OEM spring seat.

Fitment: Mitsubishi 4G63 — 1992-2006 Evolution I-IX, 1990-1999 Eclipse GST/GSX, 1990-1998 Talon TSi, 1990-1994 Laser RS, 1991-1992 Galant VR4. Works on Evo 1-7 and 8/9 heads.

Includes 16 beehive valve springs and 16 Grade 5 titanium retainers — a full head's worth.

Do it while the head is off. If you're already in for cams or a valve job, that's the time.