Q:  How do you read the NFS Piston model numbers?

A:  NFS Piston Legend: 

Q:  What is a "Drop Forged" piston?

A:  There are several common methods used to make a piston: 

The most common method (used by factory engines) is a casting.  A cast piston is created by pouring molten aluminum into a mold using natural gravity.  This is the easiest and least expensive method, and normally produces a good quality part.  Due to their low price, cast pistons are often the choice for factory production engines.

Another type is a "billet" piston - where a piston is machined from a single solid piece of raw aluminum.  This is much more expensive and time consuming than a casting, but usually results in a stronger part than a casting, and is free from the limitations of using a pre-made mold, so a billet part is often used for custom or low-volume parts when you cannot justify the tooling expenses of a forging die.

A "drop forged" piston is created in a die using molten aluminum under very high pressure.  The high pressure compacts the grain structure of the metal into a more dense and stronger part, yielding superior strength to a cast or billet piston.  In most high performance engines where ultimate strength and durability is needed, you will see a forged piston being used.