ARP 207-4702 Pro Series Undercut Head Stud Kit – 7-Bolt Mitsubishi 4G63 (M11)

Upgrade your engine’s clamping power with the premium ARP 207-4702 Head Stud Kit for 7-bolt Mitsubishi 4G63 engines. Manufactured from 8740 chromoly steel and heat-treated to 200,000 psi tensile strength, this kit provides a major performance upgrade over factory head bolts to prevent head gasket failure under high boost.

Key Features

• 8740 Chromoly Construction: Premium-grade alloy steel rated up to 200,000 psi tensile strength for exceptional fatigue resistance.
• Precision Threads: Threads are rolled after heat treatment to ensure maximum strength and thread life.
• Engineered for 450–650 HP: Ideal for high-heat environments like road racing, autocross, and aggressive street/strip applications.
• Complete Kit: Includes 10 undercut studs, 10 parallel-ground washers, 10 12-point nuts, and ARP Ultra-Torque assembly lubricant.

Fitment & Application

Features M11 (11mm) thread sizing specifically for late-model 7-bolt 4G63 blocks.

• Fits: 1995–1999 Mitsubishi Eclipse GST/GSX & Eagle Talon TSi (2G DSM)
• Fits: Mitsubishi Lancer Evolution 4, 5, 6, 7, 8, and 9 (Evo IV–IX)

WARNING — WILL NOT FIT:

• Early 1989–1992 6-bolt blocks.
• 1992.5–1994 early 7-bolt blocks (1G DSM), which utilize M12 threads.
• Mitsubishi Lancer Evolution 1, 2, and 3 (Evo I–III), which utilize M12 threads.

Always confirm your exact engine block thread diameter (M11 vs M12) before ordering.

Manufacturer Part Number: 207-4702

What does "Undercut" mean?

The ARP 207-4702 Pro Series Undercut Head Stud Kit features a reduced-diameter, unthreaded center section on the shorter studs. By thinning this unthreaded portion, ARP matches the elasticity and stretch rate of the shorter studs to the longer ones. This engineered flexibility results in perfectly symmetrical preload and completely uniform clamping force across your head gasket, while better absorbing the aggressive thermal expansion of the 4G63 aluminum cylinder head.