Sparks Racing developed its 1,065cc Big Block Cylinder Kit as a bolt-on displacement upgrade for the original Polaris RZR XP 1000. The kit combined a purpose-built closed-deck cylinder with CP pistons and the required gaskets while retaining the factory connecting rods.
Introduced in 2014, the kit addressed one of the challenges associated with modifying the RZR XP 1000 engine. Increasing displacement with the factory cylinders normally required considerably more engine disassembly. Sparks Racing designed its replacement cylinder so the conversion could be performed without removing the engine or splitting the bottom end.
Sparks Racing 1065cc Big Bore Kit
The kit increased the RZR XP 1000’s displacement from its original 999cc configuration to 1,065cc. Its one-piece cast cylinder used a closed-deck layout intended to improve cylinder rigidity and head-gasket sealing under increased combustion pressure.
Sparks Racing offered configurations for naturally aspirated pump-gas engines, race-fuel builds and turbocharged applications. The appropriate compression ratio, engine tuning and supporting components depended on the intended setup.
Key Features
- One-piece cast cylinder
- Closed-deck construction for added cylinder rigidity
- Improved head-gasket sealing compared with an open-deck design
- Nikasil-plated cylinder bores
- Enlarged water jackets for improved heat dissipation
- Purpose-designed head gasket
- Custom CP pistons manufactured for Sparks Racing
- Configurations offered for pump fuel, race fuel and turbo applications
- Designed to work with the stock connecting rods
- No bottom-end modifications required
What the Kit Included
- Sparks Racing 1,065cc Big Block cylinder
- Pair of CP/Sparks Racing piston kits
- Head gasket
- Base gasket
Installation and Tuning Considerations
Although Sparks Racing described the package as a bolt-on kit, this was still a major internal engine modification. Correct piston selection, cylinder-head preparation, fuel delivery, ECU calibration and clutch tuning were important to the performance and durability of the finished engine.
Owners considering a used or new-old-stock kit should verify that every component is present and confirm current piston, gasket and tuning recommendations with Sparks Racing. Parts specifications and availability may have changed since the kit was introduced.
About Sparks Racing
Founded by racer and engine builder Curtis Sparks, Sparks Racing established its reputation through ATV racing and performance development. The company expanded into UTV performance parts in 2012, initially supporting the Polaris RZR XP 900 before developing products for the RZR XP 1000 and other machines.
Visit Sparks Racing for current product information and application guidance.
Editor’s note: This article covers a performance product introduced in 2014. Confirm current availability, compatibility and installation requirements directly with the manufacturer before ordering components.
