Magnum .040 (79.45mm) Piston & Top End Gasket Set


This top end rebuild kit includes a brand new .040″ OVERSIZE Namura piston with rings and piston pin.  Your cylinder will REQUIRE boring to use this piston kit!  This can be done at a machine shop locally or we can bore it for you at an additional cost, call us for details. You will also receive a top end gasket kit to rebuild the top end of your Polaris 330 four stroke motor.  Don’t ever re-use old gaskets when rebuilding your engine! High quality non-asbestos materials are used in kit.

Namura pistons are direct OEM replacements with a few key advantages.  First is the Teflon/Molybdenum coating on the skirts to increase heat transfer, reduce friction and reduces scuffing and seizures.   Machined smooth heads and anodized domes increase durability and can even add horsepower and fuel economy.  Lastly, the Hypereutectic casting process provides a higher silicon content for reduced expansion rates and additional wear resistance.  Namura pistons are simply the best value on the market.  All the advantages of a top of the line piston at a great price!

Include a new .040″ (79.45mm) Oversize piston kit and all of the following top end gaskets shown in the photo including:


  • Head Gasket
  • Base Gasket
  • Valve Cover O-Ring
  • Exhaust Gasket
  • Breather Cover Gasket
  • Valve Seals
  • Tensioner Gasket


This piston and gasket kit fits the following models:

2004-05 ATP 330

2003-06 Magnum 330


In stock

SKU: 100-4272 Category:
Magnum .040 (79.45mm) Piston & Top End Gasket Set - s-l1600-97
Magnum .040 (79.45mm) Piston & Top End Gasket Set

In stock