GSC Power Division - Mitsubishi 4G63 & 4B11

Camshafts: Billet S1, S2, S3, R1, R2 stroker, R3 stroker, R4 and L3 profiles for 4G63T (Evo 1-3, Evo 4-8, Evo 9 MIVEC) and 4B11T (Evo X).

Valves: Chrome polished and Super Alloy intake and exhaust valves in standard and +1mm head sizes.

Valve guides: Manganese bronze intake and exhaust guides in traditional, stopper and shorty stopper styles.

Springs & retainers: Conical, high pressure and extreme pressure spring kits, titanium retainers for beehive and single springs, and chromoly spring seats.

Small parts: Valve keeper sets, Viton stem seals, valve seat sets, zero-tick lifters and the race balance shaft.

Identify your engine code first. The 4G63T is used in Lancer Evolution I-IX (chassis CD9A, CE9A, CN9A, CP9A, CT9A), while the 4B11T is used in Lancer Evolution X (CZ4A). Camshafts are generation specific: Evo 1-3, Evo 4-8 and Evo 9 MIVEC heads are not interchangeable, so match the listing to your head casting. Valves and guides are listed by head diameter (STD or +1mm) and stem style, so confirm whether your head has been machined for oversize valves or stopper-style guides before ordering. If you are unsure which variant suits your build, contact us with your engine code and head specification.

These are cylinder head and valvetrain components, so installation by a professional engine builder or qualified workshop is recommended. Guides and valve seats require machining, honing and correct interference fits, while valves generally need seat cutting and lapping. Camshaft changes typically call for timing belt or chain service parts, valve clearance checks or shim adjustment, and clearance verification between valves and pistons. Spring kits may require matched seats and retainers, and any camshaft or valvetrain change should be followed by a professional ECU tune.

Will 4G63T camshafts fit a 4B11T? No. The two engines use different heads and camshaft designs, so parts must be matched to the specific engine code.

Do MIVEC (Evo 9) heads use the same cams as Evo 4-8? No. Evo 9 MIVEC heads require MIVEC-specific camshaft profiles listed separately in this collection.

Are oversize valves a straight swap? Not usually. +1mm valves generally require seat machining by an engine machinist.