WISECO MN-37J8 Top End Kit Engine Pistons Yp MN/37J8

( Brand: Wiseco ), ( Manufacturer Part Number: MN/37J8 ), ( Compatible Year: 1989 1988 1987 1986 1985 1984 ), ( Compatible Model: Pz480 Phazer ), ( Bundle Description: 1 Pc Genuine Wiseco Top End Kits ), ( Type: Top End Kits ), ( Core Charge: Free No Core Charge ), ( Fitment Type: Direct Replacement )

Review WISECO Mn/37j8 Top End Kit Yamaha Engine Pistons Yp fits PHAZER PZ480 1984–1989

The WISCO MN/37J8 Top End Kit for the 1984-1989 Yamaha PW50, PW52, PW54, PW56, PW80, and PW250 Phazer engines is a high-performance upgrade designed for enthusiasts seeking increased power, improved durability, and enhanced engine performance. This top end kit is specifically engineered for the pistons YP and is an excellent choice for those looking to breathe new life into their Phazer engine.

The WISCO MN/37J8 Top End Kit includes several key components that work together to optimize engine performance. The pistons, made from a forged aluminum alloy, are designed to provide superior strength and durability compared to stock pistons. They feature a compression height that increases engine compression, resulting in improved power output and torque.

The piston rings are another essential component of this top end kit. They are precision-manufactured to ensure a snug fit in the cylinder bore. These rings reduce the compression leakage, minimize oil consumption, and prevent blowby, ensuring optimal engine performance and longevity.

The WISCO MN/37J8 Top End Kit also includes new cylinder head gaskets, which ensure a proper seal between the cylinder head and engine block. These gaskets are engineered to provide a reliable seal while withstanding the increased engine pressures generated by the upgraded pistons.

The kit also includes new valve guides and valve seals. The valve guides are precision-machined to ensure proper valve alignment and minimize wear, while the valve seals help prevent oil leaks and ensure a tight seal between the valves and cylinder head.

In summary, the WISCO MN/37J8 Top End Kit for 1984-1989 Yamaha PW50, PW52, PW54, PW56, PW80, and PW250 Phazer engines is a comprehensive performance upgrade that includes upgraded pistons, piston rings, cylinder head gaskets, valve guides, and valve seals. This kit offers enhanced engine performance, increased power, improved durability, and reduced oil consumption, making it an excellent investment for Phazer enthusiasts looking to take their engine to the next level.

The WISCO MN/37J8 top end kit for the 1984-1989 Yamaha PW50, PW52, PW56, and PW58 Phazer engines is a popular upgrade option for those looking to improve engine performance. Here are some pros and cons of purchasing this kit:

1. Increased Power: The WISCO pistons are made of a high-performance alloy that allows for a higher compression ratio, leading to increased power output.

2. Improved Durability: The pistons are designed to be stronger and more durable than the stock pistons, reducing the likelihood of engine damage from high RPMs or heavy use.

3. Enhanced Engine Response: The improved piston design allows for better engine response, resulting in smoother power delivery and improved throttle response.

4. Cost-Effective: Compared to a full engine rebuild or replacement, the WISCO top end kit is a more cost-effective option for those looking to breathe new life into their Phazer engine.

1. Installation Complexity: Installing the top end kit requires a fair amount of mechanical knowledge and experience. It is not a simple bolt-on upgrade and may require the use of specialized tools.

2. Potential for Overheating: The increased compression ratio can lead to higher engine temperatures, especially if the engine cooling system is not up to par. Proper cooling system maintenance is essential to prevent damage.

3. Potential for Engine Knocking: If the engine is not properly tuned, the increased compression ratio can lead to engine knocking. Proper tuning is essential to ensure the engine runs smoothly and efficiently.

In conclusion, the WISCO MN/37J8 top end kit for the 1984-1989 Yamaha PW50, PW52, PW56, and PW58 Phazer engines offers significant performance improvements, increased durability, and cost-effectiveness compared to a full engine rebuild or replacement. However, it requires a fair amount of mechanical knowledge and experience for installation, and proper cooling system maintenance and engine tuning are essential to prevent engine damage or knocking.

If you are comfortable with the installation process and understand the importance of proper cooling system maintenance and engine tuning, the WISCO MN/37J8 top end kit is a great option for those looking to improve the performance and durability of their Phazer engine. However, if you are not confident in your mechanical abilities, it may be best to consult a professional mechanic or engine builder to ensure a successful installation.

Details:

Wiseco Top End Kit for 1984 - 1989 Yamaha PZ480 Phazer - Engine Pistons yp: Status: In Stock.

part #: mn37j8 prices

• $139.99-$140.79

specifications enginesnowmobile:

• for models: Pz480, Phazer
• for makes: Yamaha
• for years: 1984-1989
• brand: Wiseco
• mpn: Mn/37j8
• compatible year: 1989 1988 1987 1986 1985 1984
• compatible model: Pz480 Phazer
• bundle description: 1 Pc Genuine Wiseco Top End Kits
• type: Top End Kits
• core charge: Free No Core Charge
• fitment type: Direct Replacement

general enginesnowmobile:

• Snowmobile Parts > Engines Components > Snowmobile Engine Components
• condition: New

payments enginesnowmobile:

• credit card: Discover
• other
• wallet: Apple-pay

shipping enginesnowmobile:

• service: Standard
• class: Standard
• type: Fixed
• transit: 3-6 Days
• cost: $0.00

seller enginesnowmobile:

• city: Multiple warehouses
• rating: 96.4%
• # reviews: 9658

offer enginesnowmobile:

• started: August 24, 2025
• options: Ship-to-home
• availability: In Stock
• sold: 0
• quantity: 1

returns enginesnowmobile:

• paid by: Seller
• time: 30 Days
• policy: Returns Accepted

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