Mazworx QR25DE Block Stage 2

The Mazworx QR25DE Block Stage 2 is a precision-prepped engine block designed specifically for Nissan QR25 engines. Utilizing advanced CNC machinery and expert craftsmanship, each block undergoes extensive machining and quality checks to ensure optimal performance and durability. This product is a ready-to-assemble sleeved block, with all critical clearances verified and machining tasks completed to exacting standards.

Comprehensive Preparation Process

Each sleeved block is prepared through a detailed procedure that includes:

• Complete disassembly of the core block
• Hot tank cleaning and thorough degreasing
• Sand blasting to remove corrosion, corrosion debris, and to achieve a satin aluminum finish
• Removal of old sleeves and installation of Darton MID sleeves made of durable ductile iron
• Resizing of cylinders and line bore using 3-axis CNC equipment to ensure precision
• Honing cylinders with a Sunnen SV-10 hone fitted with diamond tooling, performed with a torque plate to simulate cylinder head clamping
• Step decking the block surface to increase clamp force reliability and improve head gasket sealing under high boost conditions

Included Components and Customer Requirements

• Included Parts: Darton MID sleeves, ARP main studs
• Customer Supplies: Core block (two pieces required)

If you plan to send in your existing block, machining will commence upon receipt. If you do not have a block, you may select one from available options when ordering.

Bore Size and Application Notes

Bore sizes can be selected according to your needs. For turbocharged applications, Mazworx recommends limiting the bore to 90mm to maintain block integrity. Our CNC boring process ensures bores are precisely centered, followed by meticulous honing to achieve an exceptional cylinder finish.

Main Studs and Line Bore Details

The block includes line boring tailored for factory girdled blocks, finished with line honing. If you do not supply your own main studs, ARP studs will be provided as part of the package.

This Stage 2 block preparation is ideal for builds targeting higher horsepower outputs, offering enhanced strength and reliability through precision machining and premium components.