N12 SneedSpeed Crate Engine

Street Series — OEM+ Reliability · Race-Proven Engineering

The SneedSpeed N12 Crate Engine is a fully assembled, professionally rebuilt long block designed for MINI Cooper R55, R56, and R57 models equipped with the naturally aspirated 1.6-liter N12 engine.

Built for owners who want to restore their MINI's original performance, reliability, and driving experience, the SneedSpeed Street Series combines precision engine machining, carefully selected replacement components, and the real-world experience gained from our MINI Cooper racing program.

The N12 is a capable, efficient engine when properly maintained and correctly assembled. Unfortunately, years of wear, timing system problems, oil consumption, and inadequate repairs can leave owners facing expensive engine failures.

SneedSpeed's solution is straightforward: rebuild the N12 correctly, address known wear and failure points, and deliver a dependable engine designed for years of everyday driving.

This isn't a used engine pulled from another MINI. It's a complete, professionally remanufactured long block built to SneedSpeed's engine assembly and inspection standards.

Race-Proven Experience. Built for the Street.

What makes the SneedSpeed N12 different from an ordinary replacement engine?

We don't just rebuild N12 engines. We race them.

SneedSpeed builds and supports MINI Cooper race cars competing in SCCA B-Spec, a racing class that emphasizes stock-based engines rather than extensive aftermarket modifications.

In B-Spec racing, engine performance and durability depend heavily on the quality of the machine work, component preparation, and assembly.

That experience gives us a practical understanding of what matters most when building a reliable N12 engine:

• Precision cylinder machining and proper piston ring seal

• Correct bearing and rotating assembly clearances

• Consistent engine lubrication and oil control

• Reliable timing chain and valvetrain operation

• Proper cylinder head preparation and sealing

• Careful inspection and verification of critical components

The same fundamentals that help an N12 survive sustained racing conditions are the fundamentals that make a dependable street engine.

Our racing experience helps us build better engines for everyday MINI owners.

Built to Restore Factory Performance & Reliability

The N12 Street Series is designed to restore the original performance and driving characteristics of your MINI Cooper.

Rather than introducing unnecessary performance modifications, we focus on returning the engine to proper operating condition through precision machining, new internal components, and careful assembly.

The result is an engine designed to deliver smooth idle quality, responsive acceleration, dependable operation, and factory-style drivability.

Whether your original engine has suffered timing system failure, excessive oil consumption, low compression, or simply accumulated too many miles, the SneedSpeed N12 Crate Engine provides a professionally rebuilt replacement.

SneedSpeed N12 Engine Build Specifications

Every N12 Street Series engine is assembled using our established machining, inspection, and assembly procedures.

Engine Block & Rotating Assembly

• Fully inspected and remanufactured N12 engine block

• Precision cylinder machining and honing

• New Street Series pistons

• New piston rings

• OEM-type connecting rods

• New engine bearings

• Balanced rotating assembly

• Verified piston-to-wall and bearing clearances

• Inspection and preparation of critical sealing surfaces

Cylinder Head & Valvetrain

• Fully remanufactured N12 cylinder head

• Inspection of valves, guides, and valve seats

• OEM camshafts

• OEM-specification valve springs

• Inspection of valvetrain components

• Factory-style valve timing and operation

Assembly & Quality Standards

• New gaskets and seals

• Inspection of critical oiling components

• Attention to common N12 wear and failure points

• Precision assembly and clearance verification

• SneedSpeed final inspection standards

• Fully assembled long block, ready for installation

Every engine is built with attention to the details that affect long-term reliability, oil control, compression, and overall engine performance.

Why Precision Engine Building Matters

A replacement engine is only as good as the work performed inside it.

Simply installing new parts into a worn engine block does not correct cylinder wear, improper clearances, poor sealing surfaces, or underlying mechanical problems.

SneedSpeed takes a more complete approach.

We inspect and prepare the major engine components, verify critical measurements, and assemble the engine around the specifications required for dependable operation.

Our focus includes:

• Cylinder Condition: Proper machining and honing help establish reliable piston ring sealing and oil control.

• Bearing Clearances: Correct clearances support consistent lubrication and long-term rotating assembly durability.

• Cylinder Head Condition: Proper inspection and remanufacturing help restore compression and efficient engine operation.

• Timing System Integrity: Correct assembly and timing verification help address one of the N12 platform's most important reliability concerns.

• Engine Balance: A balanced rotating assembly helps reduce vibration and supports smooth engine operation.

These details may not be visible once the engine is installed, but they are essential to how it performs and how long it lasts.

Factory Driving Characteristics

The SneedSpeed N12 Street Series retains the original naturally aspirated engine configuration.

This means the engine is designed to work with the factory engine management, intake, exhaust, and supporting systems.

What You Can Expect

• Factory-style idle and drivability

• Smooth, predictable power delivery

• Original engine performance capability

• Compatibility with factory engine management

• Reliable operation for everyday driving

• A professionally rebuilt foundation for long-term ownership

The goal is not to turn your naturally aspirated MINI into a race car.

The goal is to make your MINI drive the way it should again.

N12 Street Series Specifications

Applications

Designed for MINI Cooper models equipped with the naturally aspirated N12 engine, including:

• R55 MINI Cooper Clubman

• R56 MINI Cooper Hatchback

• R57 MINI Cooper Convertible

• N12-powered MINI Cooper models requiring a replacement long block

Applications vary by model year and production date. Verify your engine code before ordering, as later MINI Cooper models may use the N16 engine.

Who Is This Engine For?

The SneedSpeed N12 Street Series is ideal for:

• MINI Cooper owners replacing a failed engine

• High-mileage vehicles experiencing engine wear

• Engines with excessive oil consumption

• Vehicles suffering from low compression or internal engine damage

• Owners restoring their MINI to factory driving condition

• Daily drivers requiring a dependable replacement engine

• Enthusiasts who want to keep their naturally aspirated MINI on the road

For dedicated SCCA B-Spec competition applications, SneedSpeed also offers a separate N12 B-Spec Race Engine built specifically for stock-based racing requirements.

Why Choose a SneedSpeed N12 Crate Engine?

SneedSpeed has spent years building, developing, and racing MINI engines.

Our experience goes beyond installing replacement parts. We understand how these engines operate, where they experience wear, and which assembly details make the greatest difference in reliability.

The N12 Street Series benefits from that experience without requiring expensive racing components or unnecessary modifications.

You receive a professionally remanufactured engine designed around the original MINI Cooper driving experience, built with the same attention to precision that our racing program demands.

SneedSpeed N12 Crate Engine — Race-Proven Knowledge. Factory Performance. Built for the Road.