ICON Forged Pistons for GM LS: Custom Piston Features at an Off-the-Shelf Price

You don’t have to spend a ton of money to fit high-quality pistons in your LS engine. ICON offers FHR Series and Premium Forged Pistons that have many of the features high-dollar custom pistons have—except the price tag. Both types have ICON’s UltraWear42 skirt coating which helps the pistons operate in temperatures over 2,000 degrees and withstand an incredible 250,000 PSI.

FHR Series Piston and Ring Sets
ICON’s FHR Series piston and ring sets give you the benefits of a custom-made forged piston at an affordable, off-the-shelf price. FHR stands for Formed Head Relief, a process where the valve reliefs are formed as the piston blank is pressed into the die, creating a strong, light forging. Many of the pistons with domed heads are solid, which allows ICON to tailor the dome height for specific compression ratios.

FHR Series Pistons are forged from low-expansion 4032 aluminum alloy to maintain tighter piston-to-wall clearances. That means better cylinder sealing, lower cylinder wear, and OEM noise levels, making them ideal for street and lightly boosted applications.

Other features include:
• Ring grooves, ring lands, pin holes, and skirt profiles are diamond-machined to dimensional tolerances as low as .0001"
• Optimized material and grain flow in high stress sections to handle high compression, mild boost, and nitrous
• Accumulator grooves reduce gas pressure between the top and second ring to help stabilize the top ring and maximize ring seal
• Precision forged crowns with oversized valve pockets for larger valves found in aftermarket heads
• Low-friction, high-adhesion molybdenum skirt coating reduces dry startup scuffing
• .030" offset wrist pins to reduce piston ‘slap’
• Sets are weight-matched to within +/- 2 grams for vibration-free operation
• Low-friction 1.5mm x 1.5mm x 3mm ring sets.
• Wrist pins and wire locks included

Premium Forged Piston and Ring Kits
Developed with major engine builders to provide maximum compression and performance, ICON Premium Piston and Ring Sets are designed for high performance street and race use. The pistons are made from high-strength 2618 billet aluminum alloy with lower silicon content, which makes them better suited for engine combinations with high compression or a power adder.

Features include:
• Fully CNC-machined valve reliefs and crowns
• Polished piston crowns help maximize combustion efficiency
• Diamond-finished skirts
• Second land accumulator groove
• Top land mini groove technology
• Triple wound spiral locks
• Dual forced pin oiling on most applications
• Lateral gas porting on higher compression ratios
• Oil support rings included for applications where the wrist pin intersects the oil groove

The piston ring sets come with a 1/16 inch plasma-moly coated ductile iron top ring, a 1/16 inch cast iron secondary ring, and a 3/16 inch stainless steel oil control ring.