HKS 4U-GSE 2.1L Capacity Upgrade Kit 86.0mm Pistons

Capacity Upgrade Kit developed by taking advantage of knowledge and experience acquired through D1 drift and time attack at Tsukuba Circuit. This kit was designed exclusively for the engine by meticulous analysis and experiment. HKS delivers this kit with "Made in Japan" quality. High performance specifications withstanding 550(ps)-50(kgf・m)!
This kit is for people want to upgrade all the way including the engine internals.

Features

POINT-1:PISTON KIT

• Carefully selected specially forged raw materials used
• Replacing the gasket enables both NA and turbo-charged engine users to use this kit.
• In order to cope with the demands of high outputs, strength analysis and tests have allowed optimisation of compression ratio for flexibility of setup and high boost use.
• Piston crown had 3D design in consideration of stock direct injection system.
• Stock pistons skirts overhang from the block during bottom of travel. Short height pistons have revised potential issues in this area.
• Friction, weight and other design properties to suit the needs of short height pistons.

POINT-2:CONNECTING ROD

• Specific connecting rods have been designed to suit the longer stroke. 
  With no engine modifications, a special size crank pin has been set requiring new bearings.
  ※The crank metals (Nissan RB26 & SR) must be purchased separately.
• High strength I beam design and revised connecting rod bolt size.

POINT-3:CRANKSHAFT STROKE 90.0mm

• Made from HKS special forged material
• Perfect pin journal size was selected by merticulous analysis and experiment for extended stroke.
• Carefully designed weights balance the engine for maximum efficiency.

POINT-4:Stock Bore Compatible 86.0mm

• In order to maintain the engine block strength, the stock bore size is maintained meaning there is no need for cylinder liners
• Reduces the cost of installation as liners, bore & hone and block facing processes are unnecessary