Andrews TW31 Cams for 1999-2006 Harley Twin Cam

Product Description

Andrews TW31S Chain Drive Cam Set for Harley Twin Cam

Upgrade your early Harley-Davidson Twin Cam with the Andrews TW31S Chain Drive Cam Set. Designed for performance-oriented street engines, the TW31S delivers a strong combination of midrange torque and upper-rpm horsepower while maintaining manageable valve lift and compatibility with stock valve springs.

The TW31S is an excellent choice for 95ci engines with approximately 9.8:1 to 10.2:1 compression. With .510" intake and exhaust lift and a power range of approximately 2,400-5,600 rpm, this cam set is designed for riders looking for stronger acceleration through the midrange and improved horsepower at higher engine speeds without moving to a high-lift valvetrain combination.

Fitment

• Fits 1999-2006 Harley-Davidson Twin Cam models with the early chain-drive cam system
• Fits select Harley-Davidson Touring, Softail and Dyna models
• Does not fit 2006 Harley-Davidson Dyna models, which use the later cam drive configuration
• Compatible with carbureted and fuel-injected applications
• Compatible with stock Harley-Davidson hydraulic lifters and valve springs
• 1999 Twin Cam applications require a splined cam drive sprocket
• 1999 Sprocket Requirement: Harley-Davidson OEM #25716-99 or compatible Andrews sprocket
• Installer must verify coil bind, valve-to-valve clearance and valve-to-piston clearance during installation

Features

• TW31S performance camshaft grind
• Excellent choice for 95ci engines with approximately 9.8:1 to 10.2:1 compression
• Strong midrange torque and upper-rpm horsepower
• Designed for approximately 2,400-5,600 rpm operation
• Lower TDC lift helps simplify installation
• Compatible with stock Harley-Davidson hydraulic lifters
• Compatible with stock valve springs
• Works with carbureted and fuel-injected Twin Cam engines
• CNC-ground performance cam profiles
• Manufactured from high-quality alloy steel billets
• Heat treated for strength and durability
• Cam set includes new bearings and thrust washers
• Andrews Part Number: 288131

Specifications

• Manufacturer: Andrews Products
• Part Number: 288131
• Grind: TW31S
• Drive Type: Chain Drive
• Intake Timing @ .053": 10° / 46°
• Exhaust Timing @ .053": 52° / 8°
• Intake Duration @ .053": 236°
• Exhaust Duration @ .053": 240°
• Intake Duration @ .020": 272°
• Exhaust Duration @ .020": 276°
• Intake Valve Lift: .510"
• Exhaust Valve Lift: .510"
• Intake Lift at TDC: .131"
• Exhaust Lift at TDC: .120"
• Valve Springs: Stock Compatible
• Recommended Engine: 95ci with approximately 9.8:1-10.2:1 compression
• Power Range: Approximately 2,400-5,600 rpm