Description
If you’re serious about extracting maximum horsepower from your M8, this bolt-on big bore kit delivers measurable performance gains without requiring case machining. The 4.250″ bore, forged pistons, and purpose-built oil cooling system work together to support higher RPMs and sustained power delivery. This is a complete system engineered for reliability under racing conditions—not a collection of aftermarket parts.
Technical Specifications:
- Bore diameter: 4.250″
- Piston construction: Forged
- Compression ratio: 11.1:1
- Installation: Bolt-on, no case machining
- Oil pump: Precision billet aluminum
- Cam plate: Precision billet aluminum
- Oil delivery: Increased flow capacity
- Oil scavenging: Dual independent sections
- Debris protection: Screens on both pickups
- Debris protection: Magnet in cam chest
- Pressure relief: Adjustable in-engine
- Pushrods: S&S Quickee design
- Tappets: S&S premium grade
- Tappet cuffs: Billet aluminum
- Tappet cup benefit: Reduced distortion
- High-RPM stability: Enhanced
- Camshaft: S&S 550 profile
- Cam application: Big bore optimized
- Manufacturer part number: 310-1109B







