FLI Stage 3 Shortblock

Supports up to 550-850 Flywheel Horsepower.

With years of research and development, FLI now offers our Stage 3 shortblock for any 02-07 Subaru WRX, STI, XT or LGT. This block offers something that other competitors do not, Darton iron sleeves and the optional aluminum closed desk plate process with zero tolerance fitment. When running 25-35psi of boost with large turbo setups, you create very high cylinder pressure. FLI has done the research and figured out that closing the deck greatly helps this. For high horsepower race applications, FLI recommends the closed deck block with iron sleeves, which can support 850 flywheel horsepower.

All FLI Stage 3 shortblocks comes with 8.2:1 compression, unless customer specifies a change.

Features

• Brand-new EJ25 "STI" Semi-closed Block (2.5L Displacement)
• Darton Iron sleeves (optional closed desk process w/ zero tolerance fitment)
• Cosworth H Beam Billet Steel Rods (optional Arrow Titanium 6AL-4V Forged Connecting Rods 30% lighter)
• 100mm Coated Custom Forged Aluminum Pistons
• Heavy-Duty Chromoly Piston Pins
• Low Friction Piston Rings
• Coated Rod and Main Bearings
• STI 79mm Stroke Forged Chromoly Crankshaft (optional 79mm Cosworth lightweight forged steel)
• Standard 11mm ARP head studs
• Cosworth metal head gaskets

All FLI shortblock’s come fully assembled which means there is no core charge.