JE Pistons are specifically engineered for extreme applications up to, and including, professional competition. In this environment, the higher compression ratios necessitate the use of high tensile strength 2618 aluminium alloy, which is stronger than the widely used 4032 alloy.

What is traditionally seen as the only major downside to using the stronger 2618 alloy is that, due to the higher thermal expansion rate (vs 4032 alloy), 2618 pistons are normally installed with a larger piston:wall clearance which can result in 'piston slap' on cold startup. However JE's 'Perfect Skirt' coating means that the pistons can be installed with the same or less clearance than an oem cast piston as measured on the coating. Perfect Skirt is a solvent-based coating that is permanently applied to the piston skirts in a 3-stage bonding process. Unlike many coatings, it is not a temporary layer for break-in. It will stay bonded to the piston throughout its service life. The coating conforms to the cylinder on initial startup to provide a precise fit in the bore and significantly reduces friction, wear and noise.

The piston dome requires no deburring or preparation and features smooth flowing radii for excellent flame travel.

Supplied as a set of 4 pistons. Wrist pins, wire locks, and 'JE pro seal' piston rings included.

Fitting requires either adjustment to or removal of the piston oil squirters.

Specifications:

• 2618 alloy
• JE 'Perfect Skirt' coating
• JE Pro Seal piston rings
• 83.00mm bore
• 12.8:1 compression ratio
• 4.8cc piston dome
• 30.2mm compression height
• 311g weight
• FSR (forged side relief) piston design